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Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 8 Periodic Classification of Elements

Samacheer Kalvi 10th Science Periodic Classification of Elements Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
The number of periods and groups in the periodic table are:
(a) 6, 16
(b) 7, 17
(c) 8, 18
(d) 7, 18
Answer:
(d) 7, 18

Question 2.
The basis of modem periodic law is ____.
(a) atomic number
(b) atomic mass
(c) isotopic mass
(d) number of neutrons.
Answer:
(a) atomic number

Question 3.
……….. group contains the member of the halogen family.
(a) 17th
(b) 15th
(c) 18th
(d) 16th
Answer:
(a) 17th

Question 4.
_______ is a relative periodic property.
(a) atomic radii
(b) ionic radii
(c) electron affinity
(d) electronegativity.
Answer:
(b) ionic radii

Question 5.
Chemical formula of rust is:
(a) Fe0.xH₂O
(b) Fe04.xH₂O
(c) Fe₂O₃. xH₂O
(d) FeO
Answer:
(c) Fe₂O₃. xH₂O

Question 6.
In the aluminothermic process the role of Al is:
(a) oxidizing agent
(b) reducing agent
(c) hydrogenating agent
(d) sulphurising agent
Answer:
(b) reducing agent

Question 7.
The process of coating the surface of the metal with a thin layer of zinc is called ____.
(a) painting
(b) thinning
(c) galvanization
(d) electroplating.
Answer:
(c) galvanization

Question 8.
Which of the following inert gas has electrons in the outermost shell?
(a) He
(b) Ne
(c) Ar
(d) Kr
Answer:
(a) He

Question 9.
Neon shows zero electron affinity due to ____.
(a) stable arrangement of neutrons
(b) stable configuration of electrons
(c) reduced size
(d) increased density.
Answer:
(b) stable configuration of electrons

Question 10.
……….. is an important metal to form amalgam.
(a) Ag
(b) Hg
(c) Mg
(d) Al
Answer:
(b) Hg

II. Fill in the blanks:

1. If the electronegativity difference between two bonded atoms in a molecule is greater than 1.7, the nature of bonding is ………..
2. …………. is the longest period in the periodical table.
3. ………… forms the basis of modern periodic table.
4. If the distance between two Cl atoms in Cl₂ molecule is 1.98 Å, then the radius of Cl atom is ………..
5. Among the given species A^– A⁺, and A, the smallest one in size is ……….
6. The scientist who propounded the modern periodic law is …………
7. Across the period, ionic radii ………… (increases,decreases).
8. ……….. and ………… are called inner transition elements.
9. The chief ore of Aluminium is ………….
10. The chemical name of rust is ………….
Answer:
1. ionic
2. 6th (sixth) period
3. Atomic number
4. 0.99 Å
5. A⁺
6. Dimitri Mendeleev
7. decreases
8. Lanthanides, Actinides
9. bauxite
10. hydrated ferric oxide

III. Match the following:

Answer:
A. (ii)
B. (v)
C. (iv)
D. (iii)
E. (i)

IV. True or False: (If false give the correct statement)

1. Moseley’s periodic table is based on atomic mass.
2. Ionic radius increases across the period from left to right.
3. All ores are minerals; but all minerals cannot be called as ores.
4. Aluminium wires are used as electric cables due to their silvery white colour.
5. An alloy is a heterogenous mixture of metals.
Answer:
1. False – Moseley’s periodic table is based on atomic number.
2. True
3. True
4. False – Aluminium wires are used as electric cables because it is a good conductor of heat and electricity.
5. False – An alloy is an homogeneous mixture of metals.

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: The nature of bond in HF molecule is ionic.
Reason: The electronegativity difference between H and F is 1.9.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: Magnesium is used to protect steel from rusting.
Reason: Magnesium is more reactive than iron.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 3.
Assertion: An uncleaned copper vessel is covered with greenish layer. Reason: copper is not attacked by alkali.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

VI. Short answer questions:

Question 1.
A is a reddish brown metal, which combines with O₂ at < 1370 K gives B, a black coloured compound. At a temperature > 1370 K, A gives C which is red in colour. Find A, B and C with reaction.
Answer:
(A) is a reddish brown metal – Copper

A – Copper; B – Cupric oxide; C – Cuprous oxide.

Question 2.
A is a silvery white metal. A combines with O₂ to form B at 800°C, the alloy of A is used in making the aircraft. Find A and B.
Answer:
A – Silvery white metal – Aluminium

The alloys of aluminium, Duralumin and Magnalium are used in making the aircraft.
A – Aluminium; B – Aluminium oxide.

Question 3.
What is rust? Give the equation for the formation of rust.
Answer:
When iron is exposed to moist air, it forms a layer of brown hydrated ferric oxide on its surface. This compound is known as rust and the phenomenon of formation of rust is known as rusting.
4Fe + 3O₂ + xH₂O → 2Fe₂O₃. xH₂O (Rust).

Question 4.
State two conditions necessary for rusting of iron.
Answer:
(i) The presence of water and oxygen is essential for the rusting of iron.
(ii) Impurities in the iron, the presence of water vapour, acids, salts and CO₂ speeds up rusting.

VII. Long answer questions:

Question 1.
(a) State the reason for addition of caustic alkali to bauxite ore during purification of bauxite.
Answer:
Caustic alkali is added to bauxite, to dissolve bauxite ore and obtain a solution of sodium aluminate.

(b) Along with cryolite and alumina, another substance is added to the electrolyte mixture. Name the substance and give one reason for the addition.
Answer:
CaF₂ (Fluorspar) is added along with cryolite and alumina. It is added to reduce the high melting point of the electrolyte.

Question 2.
The electronic configuration of metal A is 2, 8, 18, 1.
The metal A when exposed to air and moisture forms B a green layered compound. A with con. H₂SO₄ forms C and D along with water. D is a gaseous compound. Find A, B, C and D.
Answer:
Metal (A) with electronic configuration- 2, 8, 18, 1 is copper.
2Cu + O₂ + CO₂ + H₂O → CuCO₃. Cu(OH)₂ (B)
Copper carbonate (Green layer)

(A) – Copper (Cu)
(B) – Copper Carbonate (CuCO₃. Cu(OH)₂)
(C) – Copper Sulphate (CuSO₄)
(D) – Sulphur dioxide (SO₂)

Question 3.
Explain the smelting process.
Answer:
The roasted ore of copper is mixed with powdered coke and sand and is heated in a blast furnace to obtain matte (Cu₂S + FeS) and slag. The slag is removed as waste.
2 FeS + 3O₂ → 2 FeO + 2 SO₂
2 Cu₂S + 3O₂ → 2 Cu₂O + 2SO₂
Cu₂O + FeS → Cu₂S + FeO
FeO + SiO₂ → FeSiO₂ (slag)

VIII. HOT questions:

Question 1.
Metal A belongs to period 3 and group 13. A in red hot condition reacts with steam to form B. A with strong alkali forms C. Find A, B and C with reactions.
Answer:
Metal A belongs to Period 3 and Group 13. So metal ‘A’ is aluminium.
(A) in red hot condition reacts with steam to form ‘B’.

‘A’ with strong alkali forms ‘C’

(A) – Aluminium
(B) – Aluminium oxide
(C) – Sodium meta aluminate

Question 2.
Name the acid that renders aluminium passive. Why?
Answer:
Dilute or concentrated nitric acid (HNO₃) renders aluminium passive. Because nitric acid does not attack aluminium but it renders aluminium passive due to the formation of an oxide film on its surface.

Question 3.
(a) Identify the bond between H and F in HF molecule.
Answer:
Ionic, because the electronegativity difference is more than 1.7.

(b) What property forms the basis of identification?
Answer:
Electronegativity.

(c) How does the property vary in periods and in groups?
Answer:
In a period, from left to right the electronegativity increases because of the increase in the nuclear charge.
In a Group, from top to bottom, the electronegativity decreases because of the increase in size of the elements.

Samacheer Kalvi 10th Science Periodic Classification of Elements Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The shortest period in the periodic table contains elements.
(a) 18
(b) 8
(c) 2
(d) 32
Answer:
(c) 2

Question 2.
Group number of carbon family is _____.
(a) 13
(b) 15
(c) 17
(d) 14.
Answer:
(d) 14.

Question 3.
The ore forming elements, chalcogens are present in ……… group of the modern periodic table.
(a) 18th
(b) 1st
(c) 2nd
(d) 16th
Answer:
(d) 16th

Question 4.
Valency of all the alkali metals is _____.
(a) 1
(b) 2
(c) 3
(d) 4.
Answer:
(a) 1

Question 5.
The largest atom in the 2nd period of the periodic table is:
(a) Li
(b) Be
(c) F
(d) Ne
Answer:
(a) Li

Question 6.
The covalent radii of Hydrogen, if the distance between the Hydrogen nuclei of the molecule is 0.74 Å is:
(a) 1.58 Å
(b) \(\frac{0.74}{4}\) Å
(c) 0.37 Å
(d) 0.74 Å
Answer:
(c) 0.37 Å

Question 7.
Pick out the correct ionic radii in increasing order for the following species – Na, Cl, Na⁺, Cl^– _____.
(a) Na > Cl > Na⁺ > Cl^–
(b) Cl > Na > Na⁺ > Cl^–
(c) Cl^– > Na > Na⁺ > Cl
(d) Cl < Na⁺ < Cl^– < Na.
Answer:
(d) Cl < Na⁺ < Cl^– < Na.
Hint:
Na = 186 pm,
Cl = 91 pm,
Na⁺ = 116 pm,
Cl^– = 167 pm.

Question 8.
In the third period, the first ionization potential is of the order:
(a) Na > Al > Mg > Si > P
(b) Mg > Na > Si > P > Al
(c) Na < Al < Mg < Si < P
(d) Na < Al < Mg < Si < P
Answer:
(c) Na < Al < Mg < Si < P

Question 9.
Which one of the following is the least electronegative element?
(a) Bromine
(b) Chlorine
(c) Iodine
(d) Hydrogen
Answer:
(d) Hydrogen

Question 10.
Which is a widely used a scale to determine the electronegativity?
(a) Pauling scale
(b) Moseley scale
(c) Mendeleev scale
(d) none of these.
Answer:
(a) Pauling scale

Question 11.
Which one of the following orders of ionic radii is correct?
(a) H^– > H⁺ > H
(b) Na⁺ > F^– > O^2-
(c) F > O^2- > Na⁺
(d) None of these
Answer:
(d) None of these

Question 12.
The percentage of carbon in Pig iron is:
(a) < 0.25%
(b) 0.25 – 2%
(c) 2 – 4.5%
(d) > 5%
Answer:
(c) 2 – 4.5%

Question 13.
The chemical formula of clay is _____.
(a) Al₂O₃
(b) Al₂O₃.2H₂O
(c) Al₂O₃. 2SiO₂.2H₂O
(d) Al₂O₃. 2SiO₂.H₂O.
Answer:
(c) Al₂O₃. 2SiO₂.2H₂O

Question 14.
The temperature in the combustion zone is maintained at:
(a) 1500°C
(b) 400°C
(c) 1000°C
(d) 1380°C
Answer:
(a) 1500°C

Question 15.
Oil used in Froth floatation method is _____.
(a) pine oil
(b) natural oil
(c) crude oil
(d) Synthetic oil.
Answer:
(a) pine oil

Question 16.
The first most abundant metal present in the Earth crust is:
(a) Iron
(b) Aluminium
(c) Zinc
(d) Copper
Answer:
(b) Aluminium

Question 17.
……….. metal is used for making calorimeters.
(a) Copper
(b) Tin
(c) Mercury
(d) Iron
Answer:
(a) Copper

Question 18.
More reactive metal is _____.
(a) Zn
(b) Fe
(c) Ag
(d) Na.
Answer:
(d) Na.

Question 19.
The chief ore of Iron is:
(a) Magnesite
(b) Galena
(c) Cinnabar
(d) Haematite
Answer:
(d) Haematite

Question 20.
The metal which melts at room temperature is:
(a) Zinc
(b) Lead
(c) Gallium
(d) Tin
Answer:
(c) Gallium

Question 21.
Conversion of bauxite into alumina is _____.
(a) Hall’s process
(b) Alumino thermic process
(c) Baeyer’s process
(d) Bessemerisation process.
Answer:
(c) Baeyer’s process

Question 22.
………. metal can be cut with knife.
(a) Potassium
(b) Gallium
(c) Mercury
(d) Gold
Answer:
(a) Potassium

Question 23.
………. is not a good conductor of heat and electricity.
(a) Silver
(b) Tungsten
(c) Copper
(d) Aluminium
Answer:
(b) Tungsten

Question 24.
Electrolyte used in Hall’s process ______.
(a) Pure alumina + molten cryolite + fluorspar
(b) Pure alumina + molten bauxite + fluorspar
(c) Pure bauxite + molten cryolite + fluorspar
(d) Pure bauxite + molten Haematite + fluorspar.
Answer:
(a) Pure alumina + molten cryolite + fluorspar

Question 25.
The foaming agent used for froth floatation process is:
(a) Coconut oil
(b) Pine oil
(c) Sodium chloride
(d) Groundnut oil
Answer:
(b) Pine oil

Question 26.
Three elements A, B and C are having the electronic configuration Is² 2s¹, Is² 2s² and Is² 2s² 2p¹ respectively. Which element will have the lowest ionization energy?
(a) A
(b) B
(c) C
(d) B and C
Answer:
(a) A

Question 27.
Metal used in household utensils is ______.
(a) Al
(b) Co
(c) Fe
(d) Na.
Answer:
(a) Al

Question 28.
Which one of the following pair is a metalloid?
(a) Na and K
(b) F and Cl
(c) Cu and Hg
(d) Si and Ge
Answer:
(d) Si and Ge

Question 29.
The highly metallic element will have the configuration of:
(a) 2, 8, 7
(b) 2, 8, 8, 5
(c) 2, 8, 8, 1
(d) 2, 8, 2
Answer:
(c) 2, 8, 8, 1

Question 30.
The metal used in electroplating is ______.
(a) Cu
(b) Al
(c) Fe
(d) Co.
Answer:
(a) Cu

Question 31.
The flux which is used when the gangue present in the ore is acidic:
(a) Silica
(b) Calcium oxide
(c) Calcium silicate
(d) Cuprous sulphide
Answer:
(b) Calcium oxide

Question 32.
Matte is a mixture of:
(a) Cu₂O + Cu₂S
(b) Cu₂O + FeS
(c) Cu₂S + FeS
(d) Cu₂O + PbS
Answer:
(c) Cu₂S + FeS

Question 33.
Fe reacts with dilute nitric acid in cold condition to give ______.
(a) Ferrous nitride
(b) Ferrous nitrate
(c) Ferric nitride
(d) Ferric nitrate.
Answer:
(b) Ferrous nitrate

Question 34.
In the brass alloy, which is solvent?
(a) Zn
(b) Co
(c) Ag
(d) Cu.
Answer:
(d) Cu.

II. Fill in the blanks:

1. The major component of the matte is ………….
2. The modern periodic table is based on ………..
3. The valency of alkali metals is …………
4. The unreactive elements are present in group ………..
5. In the 2nd period, the smallest atom is ……….
6. The size of a cation is ………… than the neutral atom.
7. ……….. is the unit of ionization energy.
8. The ionization energy ……… down the group in the periodic table.
9. The electron affinities of noble gases are …………
10. ………. is the process of extracting the ore from the Earth’s crust.
11. Galena is the ore of …………..
12. The silvery white metal which is a good conductor of heat and electricity is …………
13. The slag formed during Bessemerisation process is ………….
14. Blister copper contains ………. percentage of copper.
15. Haematite ore is concentrated by ……….. washing.
Answer:
1. Cu₂S
2. atomic number
3. one
4. 18
5. Neon
6. smaller
7. KJ/mol
8. decreases
9. zero
10. Mining
11. lead
12. aluminium
13. Iron silicate or FeSiO₃
14. 98%
15. hydraulic

III. Match the following:

Question 1.
Match the column I with column II.

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

Question 2.
Match the column I with column II.

Answer:
A. (ii)
B. (iv)
C. (v)
D. (iii)
E. (i)

Question 3.
Match the column I with column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (i)
E. (ii)

Question 4.
Match the column I with column II.

Answer:
A. (v)
B. (iv)
C. (ii)
D. (iii)
E. (i)

IV. True or false. (If false give the correct statement)

1. Alkali metals are generally extracted by the electrolysis of their ores in fused state.
2. Every mineral is an ore but every ore is not a mineral.
3. Slag is a product formed during smelting by combination of flux and impurities.
4. Reactive metals occur in native state.
5. Malachite is a sulphide ore of copper.
6. Lanthanides are present in the 6th group of the periodic table.
7. Atomic radius increases as we go across the period due to increase in size.
8. As the positive charge increases, the size of the cation decreases.
9. If the difference in electronegativity is greater than 1.7, the bond is considered to be covalent.
10. Siderite is the carbonate ore of calcium.
Answer:
1.True
2. True
3. True
4. False – Reactive metals always occur in the combined state.
5. False – Malachite is the carbonate ore of copper.
6. False – Lanthanides are present in the 6th period of the periodic table.
7. False – Atomic radius increases as we go across the period due to decrease in size.
8. True
9. False – If the difference in electronegativity is greater than 1.7, the bond is considered to be ionic.
10. False – Siderite is the carbonate ore of Iron.

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: Zinc blende is concentrated by Froth floatation process.
Reason: Zinc blende is a sulphide ore.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: In thermite welding, aluminium powder and Fe₂O₃ are used.
Reason: Aluminium powder is a strong reducing agent.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 3.
Assertion: To design the body of an aircraft, aluminium alloys are used.
Reason: Aluminium becomes passive when it is treated with dil or con.HNO₃
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.

Question 4.
Assertion: Tinstone and the impurity wolframite are seperated by magnetic separation.
Reason: Tinstone is magnetic and wolframite is non-magnetic in nature.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 5.
Assertion: Bauxite is purified by leaching.
Reason: Bauxite undergoes thermal decomposition.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(b) Assertion is correct, Reason is wrong.

VI. Short answer questions:

Question 1.
State the modern periodic law.
Answer:
The physical and chemical properties of the elements are the periodic function of their atomic number.

Question 2.
‘X’ is a silvery white metal. X reacts with O₂ to form Y. The same compound is obtained from the metal on reaction with steam with the liberation of hydrogen gas. Identify X and Y.
Answer:
(i) Silvery white metal ‘X’ is Aluminium.
(ii) It reacts with O₂ to form ‘Y’

(iii) Y can also be obtained on reaction with steam with the liberation of H₂.

Question 3.
Write any four characteristics of periods.
Answer:

• In a period, the electrons are filled in the same valence shell of all elements.
• As the electronic configuration changes along the period, the chemical properties of the elements also change.
• The atomic size of the elements in a period decreases from left to right
• In a period, die metallic character of the element decreases, while their non-metallic character increases.

Question 4.
Write the Principle of Hydraulic washing.
Answer:
The difference in the densities or specific gravities of the ore and the gangue is the main principle behind this method.

Question 5.
What are coinage metals?
Answer:
Copper, silver and gold are called coinage metals, as they are used in making coins and jewellery.

Question 6.
How will you separate tinstone from wolframite?
Answer:
Magnetic separation method. Tinstone is magnetic in nature.
Method: The crushed ore is placed over a conveyer belt which rotates around two metal wheels, one of which is magnetic. The magnetic particles are attracted to the magnetic wheel and fall separately apart from the non¬magnetic particles.

Question 7.
What are ores?
Answer:
The mineral from which a metal can be readily and economically extracted on a large scale is said to be ore.
eg. Bauxite Al₂O₃.2H₂O is the ore of Aluminium

Question 8.
Define electronegativity.
Answer:
It is the tendency of an element in a covalent bond to attract the shared pair of electrons towards itself. It is a relative property.

Question 9.
In what period and group will an element with z = 118 will be present?
Answer:
Elements with z = 118 will be present in Period number ‘7’ and Group number 18.

Question 10.
Why flux is added during metallurgy?
Answer:
Flux is the substance added to the ore to reduce the fusion temperature and to remove impurities.
e.g. CaO, SiO₂

Question 11.
State the trends in the electronegativity in a Group and period.
Answer:
In a Group: Electronegativity decreases in a group because of the increased number of energy levels.
In a Period: The electronegativity increases because the increase in the nuclear charge.

Question 12.
Write a note about smelting.
Answer:
Smelting is a process of reducing the roasted metallic oxide to metal in a molten condition. In this process, impurities are removed by the addition of flux as slag.

Question 13.
Write the formula of the ores of Aluminium.
Answer:

Question 14.
Explain the action of Aluminium with air.
Answer:
On heating at 800°C, aluminium bums in the air very brightly forming its oxide and nitride.
4Al + 3O₂ → 2Al₂O₃ (Aluminium oxide)
2Al + N₂ → 2AlN (Aluminium nitride).

Question 15.
What happen when Aluminium reacts with steam?
Answer:
When steam is passed over red hot aluminium, H₂ gas is evolved.

Question 16.
Write the reaction of Aluminium with Sodium hydroxide?
Answer:

Question 17.
Explain the electrolytic refining of copper.
Answer:
Cathode: A thin plate of pure copper metal.
Anode: A block of impure copper metal.
Electrolyte: Copper sulphate solution + dilute H₂SO₄
When an electric current is passed through the electrolytic solution, pure copper gets deposited at the cathode and the impurities are settled at the bottom of the anode as anode mud.

Question 18.
Mention the uses of Aluminium.
Answer:
Aluminium is used in

1. household utensils
2. electrical cable industry
3. making aeroplanes and other industrial machine parts.

Question 19.
What are the methods employed to make an alloy?
Answer:

1. By fusing the metals together. Eg: Brass is made by melting zinc and copper.
2. By compressing finely divided metals. Eg: wood mexai.

Question 20.
Write the components of wood metal.
Answer:
Wood metal is an alloy of Lead, Tin, Bismuth and Cadmium.

Question 21.
What are the uses of copper?
Answer:

• Copper is used in manufacturing electric cables and other electric appliances.
• Copper is used for making utensils, containers, calorimeters and coins.
• Copper is used in electroplating.
• Copper is alloyed with gold and silver for making coins and jewels.

Question 22.
Give example for non-ferrous copper and aluminium alloys. Non-ferrous copper alloys: Brass (Cu, Zn), Bronze (Cu, Sn)
Answer:
Non-ferrous aluminium alloys: Duralumin (Al, Mg, Cu, Mn), Magnalium (Al, Mg)

Question 23.
How is rust formed?
Answer:
When iron is exposed to moist air, it forms a layer of brown hydrated Ferric oxide on its surface. This compound is known as rust.
4Fe + 3O₂ + xH₂O → 2Fe₂O₃. xH₂O (Rust).

Question 24.
Why are the alloys prepared?
Answer:

1. To modify appearance and colour.
2. To modify chemical activity.
3. To lower the melting point.
4. To increase hardness and tensile strength.
5. To increase resistance to electricity.

Question 25.
Define corrosion.
Answer:
Corrosion is the gradual destruction of metals by chemical or electrochemical reaction with the environment.

Question 26.
What are alloys? How are they prepared?
Answer:

• An alloy is a homogeneous mixture of a metal with other metals or with non-metals that are fused together. e.g. Brass is an alloy of zinc (solute) in copper (solvent)
• Alloys are prepared by fusing the metals together.
• Alloys are prepared by compressing finely divided metals one over the other.

Question 27.
Which is known as Wet corrosion or Electrochemical corrosion?
Answer:
The corrosive action in the presence of moisture is called wet corrosion. It occurs as a result of electrochemical reaction of metal with water or aqueous solution of salt or acids or bases.

Question 28.
Write a note on Cathodic protection.
Answer:
It is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible. The easily corrodible metal is called Sacrificial metal to act as anode ensuring cathodic protection.

Question 29.
What are the methods used to prevent corrosion?
Answer:
Corrosion of metals is prevented

• by coating with paints
• by coating with oil and grease
• by alloying with other metals
• by the process of galvanization
• by electroplating
• by sacrificial protection

Question 30.
A reddish brown metal ‘A’ reacts with dil.HCl in the presence of O₂ and forms the compound ‘B’. ‘B’ can also be prepared by heating the metal A with Cl₂. Identify A and B.
Answer:
Reddish brown metal ‘A’ is copper.
(A) reacts with dil.HCl in the presence of O₂ and forms CuCl₂ which is ‘B’.

(B) can also prepared by the action of Cl₂.

Question 31.
Write the uses of copper.
Answer:

1. It is extensively used in manufacturing electric cables and other electric appliances.
2. It is used for making utensils, containers, calorimeters and coins.
3. It is used in electroplating.
4. It is alloyed with gold and silver for making coins and jewels.

Question 32.
Write the name and formula of the ores of iron.
Answer:

Question 33.
Define periodicity.
Answer:
The electronic configurations of elements help us to explain the periodic recurrence of physical and chemical properties. Anything which repeats itself after a regular interval is called periodic and this behaviour is called periodicity.

Question 34.
What happens in the combustion zone during the extraction of iron.
Answer:
The temperature in the combustion zone is 150°C. In this region coke bums 02 to form CO₂, when the charge comes in contact with a hot blast of air.

Question 35.
Explain the reactions taking place in the reduction zone.
Answer:
In the upper region of reduction zone, the temperature is at 400°C. In this region CO reduces ferric oxide to form spongy iron.

Question 36.
Define Metallic radius.
Answer:
It is defined as half the distance between the nuclei of adjacent metal atoms.

Question 37.
Complete the following reactions.

1. 4Fe + 10HNO₃ → 4Fe(NO₃)₂ + ………. + 3H₂O
2. 2Fe + 6H₂SO₄ → Fe₂(SO₄)₃ + ………. + 6H₂O

Answer:

1. NH₄NO₃
2. 3SO₂

Question 38.
What happens when steam is passed over red hot iron?
Answer:
When steam is passed over red hot iron magnetic oxide is formed.
3Fe + 4H₂O (steam) → Fe₃O₄ + 4H₂↑

Question 39.
Define Electron affinity.
Answer:
Electron affinity is the amount of energy released when a gaseous atom gains an electron to form its anion. It is also measured in kJ / mol.

Question 40.
Complete the table.
Answer:

Question 41.
Define Metallurgy.
Answer:
Metallurgy is a science of extracting metals from their ores and modifying the metals into alloys for various uses, based on their physical and chemical properties and their structural arrangement of atoms.

Question 42.
Write a short note on leaching or chemical process.
Answer:
This method is employed when the ore is in a very pure form. The ore is treated with a suitable reagent such that the ore is soluble in it but the impurities are not. The impurities are removed by filtration. The solution of the ore, ie., the filtrate is treated with a suitable reagent which precipitates the ore.
E.g. Bauxite Al₂O₃.2H₂O, the ore of aluminium.

Question 43.
Relate all the four columns of the table with their unique properties.
Answer:

Question 44.
Guess Who I am?
(i) I am preserved in Kerosene.
Answer:
Sodium

(ii) My ore is leached with NaOH.
Answer:
Aluminium

(iii) I sacrifice myself to protect my friend Iron.
Answer:
Magnesium

(iv) I am being used in propellers
Answer:
Nickel steel

Question 45.
Explain the method of making alloys.
Answer:

• By fusing the metals together. E.g. Brass is made by melting zinc and copper.
• By compressing finely divided metals. E.g. Wood metal: an alloy of lead, tin, bismuth and cadmium powder is a fusible alloy.

Question 46.
Write the differences between a mineral and a ore.
Answer:

VII. Long answer questions:

Question 1.
Write the reactions taking place during Bessemerisation of copper.
Answer:
2 FeS + 3O₂ → 2FeO + 2SO₂↑

2Cu₂S + 3O₂ → 2 Cu₂O + 2 SO₂↑
2Cu₂O + Cu₂S → 6 Cu + SO₂↑

Question 2.
How do electronegativity values help to find out the nature of bonding between atoms?
Answer:

• If the difference in electronegativity between two elements is 1.7, the bond has 50% ionic character and 50 % covalent character.
• If the difference is less than 1.7, the bond is considered to be covalent.
• If the difference is greater than 1.7, the bond is considered to be ionic.

Question 3.
Explain Froth floatation with diagram.
Answer:
Principle: This process depends on the preferential wettability of the ore with oil (pine oil) and the gangue particles by water. Lighter ores, such as sulphide ores, are concentrated by this method. Eg: Zinc blende (ZnS).

Question 4.
Explain the Baeyer’s process of conversion of Bauxite into alumina.
Answer:
(i) Bauxite ore is finely ground and heated under pressure with a solution of concentrated caustic soda solution at 150°C to obtain sodium meta aluminate.
(ii) On diluting sodium meta aluminate with water, a precipitate of aluminium hydroxide is formed.
(iii) The precipitate is filtered, washed, dried and ignited at 1000°C to get alumina.

Question 5.
Explain the Hall’s Process of electrolytic reduction of alumina with diagram.
Answer:
Hall’s Process:
Aluminium is produced by the electrolytic reduction of fused alumina (Al₂O₃) in the electrolytic cell.
Cathode : Iron tank linked with graphite
Anode : A bunch of graphite rods suspended in molten electrolyte.
Electrolyte : Pure alumina + molten cryolite + fluorspar (fluorspar lowers the fusion temperature of electrolyte)

Temperature: 900 – 950 °C
Voltage used: 5 – 6 V
Overall reaction: 2 Al₂O₃ → 4 Al + 3O₂↑

Question 6.
Write the reaction involved in the middle region of blast furnace during the extraction of iron.
Answer:
The Middle Region (Fusion Zone): The temperature prevails at 1000°C. In this region, CO₂ is reduced to CO.

Limestone decomposes to calcium oxide and CO₂.

These two reactions are endothermic due to absorption of heat. Calcium oxide combines with silica to form calcium silicate slag.
CaO + SiO₂ → CaSiO₃

Question 7.
What are the three different types of iron? Write their uses.
Answer:
(i) Pig iron (Iron with 2-4.5% of carbon): It is used in making pipes, stoves, radiators, railings, manhole covers and drain pipes.
(ii) Steel (Iron with < 0.25% of carbon): It is used in the construction of buildings, machinery, transmission cables and T. V towers and in making alloys.
(iii) Wrought iron (Iron with 0.25-2% of wraught carbon): It is used in making springs, anchors and electromagnets.

Question 8.
What is corrosion? Write the chemistry behind the formation of rust.
Answer:
(i) The slow and steady destruction of a metal by chemical or electro chemical reaction with the environment.
(ii) When the surface of iron is exposed to moisture and other gases present in the atmosphere, the following chemical reaction takes place.
Fe → Fe²⁺ + 2e^–
O₂ + 2H₂O + 4e^– → 4OH^–
O₂ + 4H⁺ + 4e^– → 2H₂O
The Fe²⁺ ions are oxidised to Fe³⁺ ions.
The Fe³⁺ ions combine OH^– ions to form Fe(OH)₃. This becomes rust which is hydrated ferric oxide with the formula Fe₂O₃.xH₂O. It is a reddish brown substance.

Question 9.
Explain the methods of preventing corrosion.
Answer:
(i) Alloying : The metals can be alloyed to prevent the process of corrosion. Eg: Stainless Steel

(ii) Surface Coating : It involves application of a protective coating over the metal. It is of the following types:
(a) Galvanization: It is the process of coating zinc on iron sheets by using electric current.
(b) Electroplating: It is a method of coating one metal over another metal by passing electric current.
(c) Anodizing: It is an electrochemical process that converts the metal surface into a decorative, durable and corrosion resistant. Aluminium is widely used for anodizing process.
(d) Cathodic Protection: It is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible. The easily corrodible metal is called sacrificial metal to act as anode ensuring cathodic protection.

Question 10.
Discuss the main featured of Periods in the modern periodic table (or) long form of periodic table.
Answer:
The horizontal rows are called periods.There are seven periods in the periodic table.

1. First period (Atomic number 1 and 2): This is the shortest period. It contains only two elements (Hydrogen and Helium).
2. Second period (Atomic number 3 to 10): This is a short period. It contains eight elements (Lithium to Neon).
3. Third period (Atomic number 11 to 18): This is also a short period. It contains eight elements (Sodium to Argon).
4. Fourth period (Atomic number 19 to 36): This is a long period. It contains eighteen elements (Potassium to Krypton). This includes 8 normal elements and 10 transition elements.
5. Fifth period (Atomic number 37 to 54): This is also a long period. It contains 18 elements (Rubidium to Xenon). This includes 8 normal elements and 10 transition elements.
6. Sixth period (Atomic number 55 to 86): This is the longest period. It contains 32 elements (Caesium to Radon). This includes 8 normal elements, 10 transition elements and 14 inner transition elements (Lanthanides).
7. Seventh period (Atomic number 87 to 118): Like the sixth period, this period also accommodates 32 elements. Recently 4 elements have been included by IUPAC.

Question 11.
Discuss the main feature of Groups in the long form of periodic table.
Answer:
(i) The vertical columns in the periodic table starting from top to bottom are called groups. There are 18 groups in the periodic table.

(ii) Based on the common characteristics of elements in each group, they can be grouped as various families.

(iii) The Lanthanides and Actinides, which form part of Group 3 are called inner transition elements.

(iv) Except ‘group O’, all the elements present in each group have the same number of electrons in their valence shell and thus have the same valency. Eg: all the elements of group 1 have one electron in their valence shells (Is¹). So, the valency of all the alkali metals is ‘ 1’.

(v) As the elements present in a group have identical valence shell electronic configurations, they possess similar chemical properties.

(vi) The physical properties of the elements in a group such as melting point, boiling point and density vary gradually.

(vii) The atoms of the ‘group 0’ elements have stable electronic configuration in their valence shells and hence they are unreactive.

VIII. Hot Questions:

Question 1.
Why noble gases have zero electron affinity value?
Answer:
Noble gases show no tendency to accept electrons because the outers and p orbitals of noble gases are completely filled. No more electrons can be added to them and hence their electron affinities are zero.

Question 2.
Arrange the following ions in order of their increasing ionic radii.
Answer:
Li⁺, Mg²⁺, K⁺ Al³⁺
Al³⁺ < Li⁺ < Mg²⁺ < K⁺

Question 3.
Cationic radius is smaller than its corresponding neutral atom. Why?
Answer:
When a neutral atom lose one or more electrons it forms a cation.
Na → Na⁺ + e^–
The radius of this cation (r_Na+)is decreased than its parent atom (r_Na).
When an atom is charged to cation, the number of nuclear charges becomes greater than the number of orbital electrons. Florence the remaining electrons are more strongly attracted by the nucleus. Hence the cationic radius is smaller than its corresponding neutral atom.

Students can Download Tamil Nadu 12th Physics Model Question Paper 5 English Medium Pdf, Tamil Nadu 12th Physics Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Physics Model Question Paper 5 English Medium

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 15 in Part I are Multiple Choice Questions of one mark each.
  These are to be answered by choosing the most suitable answer from the given four
  alternatives and writing the option code and the corresponding answer
• Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered
  in about one or two sentences.
• Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered
  in about three to five short sentences.
• Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered
  in detaiL Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 70

Part – I

Answer all the questions. Choose the correct answer. [15 x 1 = 15]

Question 1.
If voltage applied on a capacitor is increased from V to 2V, Choose the correct conclusion,
(a) Q remains the same, C is doubled
(b) Q is doubled, C doubled
(c) C remains same, Q doubled
(d) Both Q and C remain same
Answer:
(c) C remains same, Q doubled

Question 2.
The electric field in the region between two concentric charged spherical shells
(a) is zero
(b) increases with distance from centre
(c) is constant
(d) decreases with distance from centre
Answer:
(d) decreases with distance from centre

Question 3.
In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be …………
(a) R
(b) 2R
(c) \(\frac{\mathbf{R}}{4}\)
(d) \(\frac{\mathbf{R}}{2}\)
Answer:
(c) \(\frac{\mathbf{R}}{4}\)

Question 4.
The vertical component of Earth’s magnetic field at a place is equal to the horizontal component. What is the value of angle of dip at this place?
(a) 30°
(b) 45°
(c) 60°
(d) 90°
Answer:
(b) 45°

Question 5.
A step-down transformer reduces the supply voltage from 220 V to 11 V and increase the current from 6 A to 100 A. Then its efficiency is
(a) 1.2
(b) 0.83
(c) 0.12
(d) 0.9
Answer:
(b) 0.83

Question 6.
Faraday’s law of electromagnetic induction is related to the …………….
(a) Law of conservation of charge
(b) Law of conservation of energy
(c) Third law of motion
(d) Law of conservation of angular momentum
Answer:
(b) Law of conservation of energy

Question 7.
The dimension of \(\frac{1}{\mu_{0} \varepsilon_{0}}\) is ……….
(a) [L T^-1]
(b) [L² T^-2]
(c) [L^-1 T]
(d) [L^-2 T²]
Answer:
(b) [L² T^-2]

Question 8.
In a Young’s double-slit experiment, the slit separation is doubled. To maintain the same fringe spacing on the screen, the screen-to-slit distance D must be changed to,…………..
(a) 2D
(b) \(\frac{\mathrm{D}}{2}\)
(c) \(\sqrt{2} \mathrm{D}\)
(d) \(\frac{\mathrm{D}}{\sqrt{2}}\)
Answer:
(a) 2D

Question 9.
The speed of light in an isotropic medium depends on,
(a) its intensity
(b) its wavelength
(c) the nature of propagation
(d) the motion of the source w.r.to medium
Answer:
(b) its wavelength

Question 10.
The mean wavelength of light from sun is taken to be 550 nm and its mean power is 3.8 x 10²⁶ W. The number of photons received by the human eye per second on the average from sunlight is of the order of ……………..
(a) 10⁴⁵
(b) 10⁴²
(c) 10⁵⁴
(d) 10⁵¹
Answer:
(a) 10⁴⁵
Hint:

Question 11.
As the intensity of incident light increases
(a) kinetic energy of emitted photoelectrons increases
(b) photoelectric current decreases
(c) photoelectric current increases
(d) kinetic energy of emitted photoelectrons decreases
Answer:
(c) photoelectric current increases
Hint: As the intensity of incident light increases, photoelectric current increases.

Question 12.
In J.J. Thomson e/m experiment, a beam of electron is replaced by that of muons (particle with same charge as that of electrons but mass 208 times that of electrons). No deflection condition is achieved only if
(a) B is increased by 208 times
(b) B is decreased by 208 times
(c) B is increased by 14.4 times
(d) B is decreased by 14.4 times
Answer:
(c) B is increased by 14.4 times
Hint: In the condition of no deflection \(\frac{e}{m}=\frac{\mathrm{E}^{2}}{2 v \mathrm{B}^{2}}\)
If m is increased by 208 times then B should be increased \(\sqrt{208}\) = 14.4 times

Question 13.
A forward biased diode is treated as
(a) An open switch with infinite resistance
(b) A closed switch with a voltage drop of 0V
(c) A closed switch in series with a battery voltage of 0.7V
(d) A closed switch in series with a small resistance and a battery.
Answer:
(d) A closed switch in series with a small resistance and a battery.

Question 14.
The variation of frequency of carrier wave with respect to the amplitude of the modulating
signal is called …………
(a) Amplitude modulation
(b) Frequency modulation
(c) Phase modulation
(d) Pulse width modulation
Answer:
(b) Frequency modulation

Question 15.
Who is the father of the modem robotics industry formed the world’s first robotic company in 1956?
(a) Joliot
(b) Cormark
(c) Engelberger
(d) Edward purcell
Answer:
(c) Engelberger

Part – II

Answer any six questions in which Q. No 17 is compulsory.

Question 16.
What is the general definition of electric dipole moment?
Answer:
The electric dipole moment vector lies along the line joining two charges and is directed from  – q to +q. The SI unit of dipole moment is coulomb meter (cm).
\(\vec{p}=q a \hat{i}-q a(-\hat{i})=2 q a \hat{i}\)

Question 17.
Calculate the electric flux through the rectangle of sides 5 cm and 10 cm kept in the region of a uniform electric field 100 NC^-1. The angle 0 is 60°. Suppose 0 becomes zero, what is the electric flux?
Answer:

Question 18.
What is meant by hysteresis?
Answer:
The phenomenon of lagging of magnetic induction behind the magnetising field is called hysteresis. Hysteresis means Tagging behind’.

Question 19.
What is meant by wattles current?
Answer:
The component of current (I_pMS sin φ), which has a phase angle of \(\frac{\pi}{2}\) with the voltage is called reactive component. The power consumed is zero. So that it is also known as ‘Wattless’ current.

Question 20.
What is Snell’s window?
Answer:
When light entering the water from outside is seen from inside the water, the view is restricted to a particular angle equal to the critical angle i_c. The restricted illuminated circular area is called Snell’s window.

Question 21.
Define work function of a metal. Give its unit.
Answer:
The minimum energy needed for an electron to escape from the metal surface is called work function of that metal. It’s unit is electron volt (eV).

Question 22.
What is meant by radioactivity?
Answer:
The phenomenon of spontaneous emission of highly penetrating radiations such as α, β and γ rays by an element is called radioactivity.

Question 23.
What is the angular momentum of an electron in the third orbit of an atom?
Answer:
Here n = 3; h = 6.6 x 10^-34 Js
Angular momentum.

Question 24.
Explain the current flow in a NPN transistor
Answer:

• The conventional flow of current is based on the direction of the motion of holes
• In NPN transistor, current enters from the base into the emitter.

Part – III

Answer any six questions in which Q.No. 27 is compulsory. [6×3 = 18]

Question 25.
Define ‘capacitance’. Give its unit.
Answer:
The capacitance C of a capacitor is defined as the ratio of the magnitude of charge on either of the conductor plates to the potential difference existing between the conductors.
\(C=\frac{Q}{V} \text { or } Q \propto V\)
The SI unit of capacitance is coulomb per volt or farad (F).

Question 26.
Distinguish between drift velocity and mobility
Answer:

SNo.	Drift Velocity	Mobility
1.	The drift velocity is the average velocity acquired by the electrons inside the conductor when it is subjected to an electric field.	Mobility of an electron is defined as the magnitude of the drift velocity per unit electric field.
2.	\(\overrightarrow{\mathrm{V}}_{d}=\vec{a} \tau\)	\(\mu=\frac{e \tau}{m} \text { or } \mu=\frac{\left|\overrightarrow{\mathrm{V}}_ {d}\right|}{\overrightarrow{\mathrm{E}}}\)
3.	It’s unit is ms-1.	It’s unit is m2 v_1 s_1

Question 27.
A coil of a tangent galvanometer of diametre 0.24 m has 100 turns. If the horizontal component of Earth’s magnetic field is 25 x 10^-6 T then, calculate the current which gives a deflection of 60°.
Answer:
The diameter of the coil is 0.24 m. Therefore, radius of the coil is 0.12 m.
Number of turns is 100 turns. Earth’s magnetic field is 25 x 10^-6 T

Question 28.
Mention the ways of producing induced emf.
Answer:
Induced emf can be produced by changing magnetic flux in any of the following ways:

• By changing the magnetic field B
• By changing the area A of the coil and
• By changing the relative orientation 0 of the coil with magnetic field

Question 29.
A 400 mH coil of negligible resistance is connected to an AC circuit in which an effective current of 6 mA is flowing. Find out the voltage across the coil if the frequency is 1000 Hz.
Answer:
L = 400 x 10^-3 H; I_eff = 6 x 10^-3A; f= 1000 Hz
Inductive reactance, X_L = Lω = L x 2πf = 2 x 3.14 x 1000 x 0.4 = 2512Ω
Voltage across L, V – IX_L = 6 x 10^-3 x 2512 =15.072 V (RMS)

Question 30.
What are the sign conventions followed for lenses?
Answer:
The sign conventions for thin lenses differ only in the signs followed for focal lengths.
(a) The sign of focal length is not decided on the direction of measurement of the focal length from the pole of the lens as they have two focal lengths, one to the left and another to the right (primary and secondary focal lengths on either side of the lens).

(b) The focal length of the thin lens is taken as positive for a converging lens and negative for a diverging lens.

Question 31.
Write down the draw backs of Bohr atom’model.
Answer:
Limitations of Bohr atom model
The following are the drawbacks of Bohr atom model

• Bohr atom model is valid only for hydrogen atom or hydrogen like-atoms but not for
  complex atoms.
• When the spectral lines are closely examined, individual lines of hydrogen spectrum is
  accompanied by a number of faint lines. These are often called fine structure. This is not explained by Bohr atom model.
• Bohr atom model fails to explain the intensity variations in the spectral lines.
• The distribution of electrons in atoms is not completely explained by Bohr atom model.

Question 32.
What do you mean by leakage current in a diode?
Answer:
The leakage current in a diode is the current that the diode will leak when a reverse voltage is applied to it. Under the reverse bias, a very small current in μA, flows across the junction. This is due to the flow of the minority charge carriers called the leakage current or reverse saturation current.

Question 33.
Distinguish between wireline and wireless communication.
Answer:

Wireline communication	Wireless communication
It is a point-to-point communication.	It is a broadcast mode communication.
It uses mediums like wires, cable and optical fibres.	It uses free space as a communication medium.
These systems cannot be used for long distance transmission as they are connected.	These systems can be used for long distance transmission.
Ex. telephone, intercom and cable TV.	Ex. mobile, radio or TV broadcasting and satellite communication.

Part – IV

Answer all the questions. [5 x 5 = 25]

Question 34.
(a) Derive an expression for the torque experienced by a dipole due to a uniform electric field.
Answer:
Torque experienced by an electric dipole in the uniform electric field: Consider an electric dipole of dipole moment \(\vec{p}\) placed in a uniform electric field \(\vec{E}\) whose field lines are equally spaced and point in the same direction. The charge +q will experience a force q\(\vec{E}\)  in the direction of the field and charge -q will experience a force -q \(\vec{E}\) in a direction opposite to the field. Since the external field \(\vec{E}\) is uniform, the total force acting on the dipole is zero. These two forces acting at different points will constitute a couple and the dipole experience a torque. This torque tends to rotate the dipole. (Note that electric field lines of a uniform field are equally spaced and point in the same direction). The total torque on the dipole about the point O.

Using right-hand corkscrew rule, it is found that total torque is perpendicular to the plane of the paper and is directed into it.
The magnitude of the total torque


where θ is the angle made by \(\vec{p} \text { with } \overrightarrow{\mathrm{E}}\) .
Since p = 2aq, the torque is written in terms of the vector product as \(\vec{\tau}=\vec{p} \times \vec{E}\)
The magnitude of this torque is τ = pE sin θ and is maximum
when θ =90°.
This torque tends to rotate the dipole and align it with the electric field [/latex]\overrightarrow{\mathrm{E}}[/latex] . Once \(\overrightarrow{\mathrm{p}}\) is aligned with \(\overrightarrow{\mathrm{E}}\), the total torque on the dipole becomes zero.

[OR]

(b) Explain the equivalent resistance of a parallel resistor network.
Answer:
Resistors in parallel: Resistors are in parallel when they are connected across the same potential difference as shown in fig. (a).
In this case, the total current I that leaves the battery in split into three separate paths. Let I₁, I₂ and I₃ be the current through the resistors R_{1 ,}R₂ and R₃ respectively. Due to the conservation of charge, total current in the circuit I is equal to sum of the currents through each of the three resistors.
I = I_{1 +} I₂ + I₃ ………………… (1)

Since the voltage across each resistor is the same, applying Ohm’s law to each resistor, we have

Substituting these values in equation (1) we get.

Here R_p is the equivalent resistance of the parallel combination of the resistors. Thus, when a number of resistors are connected in parallel, the sum of the reciprocal of the values of resistance of the individual resistor is equal to the reciprocal of the effective resistance of the combination as shown in the fig. (b).
Note: The value of equivalent resistance in parallel connection will be lesser than each individual resistance.

Question 35.
(a) Obtain a relation for the magnetic induction at a point along the axis of a circular coil ‘ carrying current.
Answer:
Magnetic field produced along the axis of the current carrying circular coil: Consider a current carrying circular loop of radius R and let I be the current flowing through the wire in the direction. The magnetic field at a point P on the axis of the circular coil at a distance z from its center of the coil O. It is computed by taking two diametrically opposite line elements of the coil each of length \(d \bar{l} \) at C and D Let r be the vector joining the current element (I \(d \bar{l}\)) at C to the point P.
PC = PD = r = \(r=\sqrt{\mathrm{R}^{2}+\mathrm{Z}^{2}}\)
PC = PD = r = \(r=\sqrt{\mathrm{R}^{2}+\mathrm{Z}^{2}}\)
angle ∠CPO = ∠DPO = θ
According to Biot-Savart’s law, the magnetic field at P due to the current element \(d \bar{l} \) is


The magnitude of magnetic field due to current element I \(d \bar{l} \) at C and D are equal because of equal distance from the coil. The magnetic field dB due to each current element I dl is resolved into two components; dB sin θ along y-direction and dB cos θ along the z-direction. Horizontal components of each current element cancels out while the vertical components (dB cos θ \(\hat{k}\) ) alone contribute to total magnetic field at the point P.
If we integrate \(d \bar{l} \) around the loop, \(d \bar{B} \) sweeps out a cone, then the net magnetic field \(\overrightarrow{\mathrm{B}}\) at point P is

Using Pythagorous theorem r² = R² + Z² and integrating line element from 0 to 2πR, we get

Note that the magnetic field \(\bar{B} \) points along the direction from the point O to P. Suppose if the current flows in clockwise direction, then magnetic field points in the direction from the point P to O.

[OR]

(b) Explain the working of a single-phase AC generator with necessary diagram.
Answer:
Single phase AC generator: In a single phase AC generator, the armature conductors are connected in series so as to form a single circuit which generates a single-phase alternating emf and hence it is called single-phase alternator.

The simplified version of a AC generator is discussed hire. Consider a stator core consisting of 2 slots in which 2 armature conductors PQ and RS are mounted to form single-turn rectangular loop PQRS. Rotor has 2 salient poles with field windings which can be magnetized by means of DC source.

Working: The loop PQRS is stationary and is perpendicular to the plane of the paper. When field windings are excited, magnetic field is produced around it. The direction of magnetic field passing through the armature core. Let the field magnet be rotated in clockwise direction by the prime mover. The axis of rotation is perpendicular to the plane of the paper.

Assume that initial position of the field magnet is horizontal. At that instant, the direction of magnetic field is perpendicular to the plane of the loop PQRS. The induced emf is zero. This is represented by origin O in the graph between induced emf and time angle.

When field magnet rotates through 90°, magnetic field becomes parallel to PQRS. The induced emfs across PQ and RS would become maximum. Since they are connected in series, emfs are added up and the direction of total induced emf is given by Fleming’s right hand rule.

Care has to be taken while applying this rule; the thumb indicates the direction of the motion of the conductor with respect to field. For clockwise rotating poles, the conductor appears to be rotating anti-clockwise. Flence, thumb should point to the left. The direction of the induced emf is at right angles to the plane of the paper. For PQ, it is downwards and for RS upwards. Therefore, the current flows along PQRS. The point A in the graph represents this maximum emf.

For the rotation of 180° from the initial position, the field is again perpendicular to PQRS and the induced emf becomes zero. This is represented by point B. The field magnet becomes again parallel to PQRS for 270° rotation of field magnet. The induced emf is maximum but the direction is reversed. Thus the current flows along SRQP. This is represented by point C.

On completion of 360°, the induced emf becomes zero and is represented by the point D. From the graph, it is clear that emf induced in PQRS is alternating in nature.

Therefore, when field magnet completes one rotation, induced emf in PQRS finishes one cycle. For this construction, the frequency of the induced emf depends on the speed at which the field magnet rotates.

Question 36.
(a) What is emission spectra? Give their types.
Answer:
Emission spectra: When the spectrum of self luminous source is taken, we get emission spectrum. Each source has its own characteristic emission spectrum. The emission spectrum _ can be divided into three types:

(i) Continuous emission spectra (or continuous spectra): If the light from incandescent lamp filament bulb) is allowed to pass through prism (simplest spectroscope), it splits into seven colours. Thus, it consists of wavelengths containing all the visible colours ranging from violet to red. Examples: spectrum obtained from carbon arc, incandescent solids, liquids gives continuous spectra.

(ii) Line emission spectrum (or line spectrum): Suppose light from hot gas is allowed to pass through prism, line spectrum is observed. Line spectra are also known as discontinuous spectra. The line spectra are sharp lines of definite wavelengths or frequencies. Such spectra arise due to excited atoms of elements. These lines are the characteristics of the element which means it is different for different elements. Examples: spectra of atomic hydrogen, helium, etc.

(iii) Band emission spectrum (or band spectrum): Band spectrum consists of several number of very closely spaced spectral lines which overlapped together forming specific bands which are separated by dark spaces, known as band spectra. This spectrum has a sharp edge at one end and fades out at the other end. Such spectra arise when the molecules are excited. Band spectrum is the characteristic of the molecule hence, the structure of the molecules can be studied using their band spectra. Examples, spectra of hydrogen gas, ammonia gas in the discharge tube etc.

[Or]

(b) Describe the Fizeau’s method to determine speed of light.
Answer:
Fizeau’s method to determine speed of light:
Apparatus: The light from the source S was first allowed to fall on a partially silvered glass plate G kept at an angle of 45° to the incident light from the source. The light then was allowed to pass through a rotating toothed-wheel with N teeth and N cuts of equal widths whose speed of rotation could be varied through an external mechanism.

The light passing through one cut in the wheel will, get reflected by a mirror M kept at a long distance d, about 8 km from the toothed wheel. If the toothed wheel was not rotating, the reflected light from the mirror would again pass through the same cut and reach the eyes of the observer through the partially silvered glass plate.

Working: The angular speed c rotation of the toothed wheel was increased from zero to a value co until light passing through one cut would completely be blocked by the adjacent tooth. This is ensured by the disappearance of light while looking through the partially silvered glass plate.

Expression for speed of light: The speed of light in air v is equal to the ratio of the distance the light travelled from the toothed wheel to the mirror and back 2d to the time taken t.
\(v=\frac{2 d}{t}\) ………………… (1)

The distance d is a known value from the arrangement. The time taken t for the light to travel the distance to and fro is calculated from the angular speed ω of the toothed wheel. The angular speed ω of the toothed wheel when the light disappeared for the first time is,
\(\omega=\frac{\theta}{t}\) ………………….. (2)

Here, θ is the angle between the tooth and the slot which is rotated by the toothed wheel within that time t

Rewriting the above equation for t
\(t=\frac{\pi}{\mathrm{N} \omega}\) ……………….. (3)
Substituting t from equation (3) in equation (1)
\(v=\frac{2 d}{\pi / \mathrm{N} \omega}\)
\(v=\frac{2 d \mathrm{N} \omega}{\pi}\) …………….(4)
Fizeau had some difficulty to visually estimate the minimum intensity blocked by the adjacent tooth, and his value for speed of light was very value.

Question 37.
(a) List out the laws of photoelectric effect.
Answer:
Laws of photoelectric effect:

• For a given frequency of incident light, the number of photoelectrons emitted is directly proportional to the intensity of the incident light. The saturation current is also directly proportional to the intensity of incident light.
• Maximum kinetic energy of the photo electrons is independent of intensity of the incident light.
• Maximum kinetic energy of the photo electrons from a given metal is directly proportional to the frequency of incident light.
• For a given surface, the emission of photoelectrons takes place only if the frequency of incident light is greater than a certain minimum frequency called the threshold frequency.
• There is no time lag between incidence of light and ejection of photoelectrons.

[OR]

(b) Describe the working of nuclear reactor with a block diagram.
Answer:
Nuclear reactor:

• Nuclear reactor is a system in which the nuclear fission takes place in a self-sustained controlled manner and the energy produced is used either for research purpose or for power generation.
• The main parts of a nuclear reactor are fuel, moderator and control rods. In addition to this, there is a cooling system which is connected with power generation set up.

Fuel:

• The fuel is fissionable material, usually uranium or plutonium. Naturally occurring uranium contains only \(0.7 \% \text { of }_{92}^{235} \mathrm{U} \text { and } 99.3 \% \text { are only }^{238} \mathrm{g}_{2} \mathrm{U}\) . So the \(_{ 92 }^{ 235 }{ U }\) must be enriched such that it contains at least 2 to 4% of \(_{ 92 }^{ 235 }{ U }\) .
• In addition to this, a neutron source is required to initiate the chain reaction for the first time. A mixture of beryllium with plutonium or polonium is used as the neutron source. During fission of \(_{ 92 }^{ 235 }{ U }\), only fast neutrons are emitted but the probability of initiating fission by it in another nucleus is very low. Therefore, slow neutrons are preferred for sustained nuclear reactions.

Moderators:

• The moderator is a material used to convert fast neutrons into slow neutrons. Usually the moderators are chosen in such a way that it must be very light nucleus having mass comparable to that of neutrons. Hence, these light nuclei undergo collision with fast neutrons and the speed of the neutron is reduced
• Most of the reactors use water, heavy water (D₂0) and graphite as moderators. The blocks of uranium stacked together with blocks of graphite (the moderator) to form a large pile.

 

Control rods:

• The control rods are used to adjust the reaction rate. During each fission, on an average 2.5 neutrons are emitted and in order to have the controlled chain reactions, only one neutron is allowed to cause another fission and the remaining neutrons are absorbed by the control rods.
• Usually cadmium or boron acts as control rod material and these rods are inserted into the uranium blocks. Depending on the insertion depth of control rod into the uranium, the average number of neutrons produced per fission is set to be equal to one or greater than one.
• If the average number of neutrons produced per fission is equal to one, then reactor is said to be in critical state. In fact, all the nuclear reactors are maintained in critical state by suitable adjustment of control rods. If it is greater than one, then reactor is said to be in super-critical and it may explode sooner or may cause massive destruction.

Shielding:

• For a protection against harmful radiations, the nuclear reactor is surrounded by a concrete wall of thickness of about 2 to 2.5 m.

Cooling system:

• The cooling system removes the heat generated in the reactor core. Ordinary water, heavy water and liquid sodium are used as coolant since they have very high specific heat capacity and have large boiling point under high pressure.
• This coolant passes through the fuel block and carries away the heat to the steam generator through heat exchanger. The steam runs the turbines which produces electricity in power reactors.

Question 38.
(a) Explain the working principle of a solar cell. Mention its applications.
Answer:
Solar cell:
A solar cell, also known as photovoltaic cell, converts light energy directly into electricity or electric potential difference by photovoltaic effect. It is basically a p-n junction which generates emf when solar radiation falls on the p-n junction. A solar cell is of two types: p-type and n-type.

Both types use a combination of p-type and n-type Silicon which together forms the p-n junction of the solar cell. The difference is that p-type solar cells use p-type Silicon as the base with an ultra-thin layer of n-type Silicon as shown in Figure, while n-type solar cell uses the opposite combination. The other side of the p-Silicon is coated with metal which forms the back electrical contact. On top of the n-type Silicon, metal grid is deposited which acts as the front electrical contact. The top of the solar cell is coated with anti-reflection coating and toughened glass.

In a solar cell, electron-hole pairs are generated due to the absorption of light near the junction. Then the charge carriers are separated due to the electric field of the depletion region. Electrons move towards n-type Silicon and holes move towards p-type Silicon layer.

The electrons reaching the n-side are collected by the front contact and holes reaching p-side are collected by the back electrical contact. Thus a potential difference is developed across solar cell. When an external load is connected to the solar cell, photocurrent flows through the load.

Many solar cells are connected together either in series or in parallel combination to form solar panel or module. Many solar panels are connected with each other to form solar arrays. For  high power applications, solar panels and solar arrays are used.

Applications:

• Solar cells are widely used in calculators, watches, toys, portable power supplies, etc.
• Solar cells are used in satellites and space applications
• Solar panels are used to generate electricity.

(b) Elaborate on the basic elements of communication system with the necessary block diagram.
Answer:
Elements of an electronic communication system
Information (Baseband or input signal): Information can be in the form of a sound signal like speech, music, pictures, or computer data which is given as input to the input transducer.

Input transducer
A transducer is a device that converts variations in a physical quantity (pressure, temperature, sound) into an equivalent electrical signal or vice versa. In communication system, the transducer converts the information which is in the form of sound, music, pictures or computer data into corresponding electrical signals. The electrical equivalent of the original information is called the baseband signal. The best example for the transducer is the microphone that converts sound energy into electrical energy.

Transmitter:
It feeds the electrical signal from the transducer to the communication channel. It consists of circuits such as amplifier, oscillator, modulator, and power amplifier. The transmitter is located at the broadcasting station.

Amplifier:
The transducer output is very weak and is amplified by the amplifier. Oscillator: It generates high-frequency carrier wave (a sinusoidal wave) for long distance transmission into space. As the energy of a wave is proportional to its frequency, the carrier wave has very high energy.

Modulator:
It superimposes the baseband signal onto the carrier signal and generates the modulated signal.

Power amplifier:
It increases the power level of the electrical signal in order to cover a large distance.

Transmitting antenna:
It radiates the radio signal into space in all directions. It travels in the form of electromagnetic waves with the velocity of light (3 ^x 10⁸ ms^-1).

Communication channel:
Communication channel is used to carry the electrical signal from transmitter to receiver with less noise or distortion. The communication medium is basically of two types: wireline communication and wireless communication.

Noise:
It is the undesirable electrical signal that interfaces with the transmitted signal. Noise attenuates or reduces the quality of the transmitted signal. It may be man-made (automobiles, welding machines, electric motors etc .) or natural (lightening, radiation from sun and stars and environmental effects). Noise cannot be completely eliminated. However, it can be reduced using various techniques.

Receiver:
The signals that are transmitted through the communication medium are received with the help of a receiving antenna and are fed into the receiver. The receiver consists of electronic circuits like demodulator, amplifier, detector etc. The demodulator extracts the baseband signal from the carrier signal. Then the baseband signal is detected and amplified using amplifiers. Finally, it is fed to the output transducer.

Repeaters:
Repeaters are used to increase the range or distance through which the signals are sent. It is a combination of transmitter and receiver. The signals are received, amplified, and retransmitted with a carrier signal of different frequency to the destination. The best example is the communication satellite in space.

Output transducer:
It converts the electrical signal back to its original form such as sound, music, pictures or data. Examples of output transducers are loudspeakers, picture tubes, computer monitor, etc.

Attenuation:
The loss of strength of a signal while propagating through a medium is known as attenuation.

Range:
It is the maximum distance between the source and the destination up to which the signal is received with sufficient strength.

Students can download 10th Social Science Civics Chapter 5 India’s International Relations Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Civics Chapter 5 India’s International Relations

Samacheer Kalvi 10th Social Science India’s International Relations Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
McMahon Line is a border between
(a) Burma and India
(b) India and nepal
(c) India and China
(d) India and Bhutan
Answer:
(c) India and China

Question 2.
India is not a member of which of the following …………..
1. G20
2. ASEAN
3. SAARC
4. BRICS
Select the correct option
(a) 4 only
(b) 2 and 4
(c) 2, 4 and 1
(d) 1, 2, and 3
Answer:
2 only

Question 3.
OPEC is:
(a) An international insurance Co.
(b) An international sports club
(c) An Organisation of Oil Exporting Countries
(d) An international company
Answer:
(c) An Organisation of Oil Exporting Countries

Question 4.
With which country does India share its longest land border?
(a) Bangladesh
(b) Myanmar
(c) Afghanistan
(d) China
Answer:
(a) Bangladesh

Question 5.
Match the following and choose the correct answer form the codes given below.

(a) 3 14 2
(b) 3 12 4
(c) 3 4 12
(d) 4 3 2 1
Answer:
(a) 3 14 2

Question 6.
How many countries share its border with India?
(a) 5
(b) 6
(c) 7
(d) 8
Answer:
(c) 7

Question 7.
Which two island countries are India’s neighbours?
(a) Sri Lanka and Andaman island
(b) Maldieves and Lakshadweep island
(c) Maldieves and Nicobar island
(d) Sri Lanka and Maldieves
Answer:
(d) Sri Lanka and Maldieves

Question 8.
Which Indian state is surrounded by three countries?
(a) Arunachal Pradesh
(b) Meghalaya
(c) Mizoram
(d) Sikkim
Answer:
(a) Arunachal Pradesh and (d) Sikkim

Question 9.
How many Indian states have their boundary with Nepal?
(a) Five
(b) Four
(c) Three
(d) Two
Answer:
(a) Five

Question 10.
Who drew up the borders for newly independent Pakistan?
(a) Lord Mountbatten
(b) Sir Cyril Radcliffe
(c) Clement Atlee
(d) None of the above
Answer:
(b) Sir Cyril Radcliffe

II. Fill in the blanks

1. ………………. is a small Himalayan kingdom.
2. India’s gateway to South East Asia is ……………….
3. ………………. is a buffer country between India and China.
4. A strip of land ………………. belongs to India on West Bengal and Bangladesh border.
5. ………………. is known as the Land of thunderbolt.
6. India and Sri Lanka are separated by ……………….

Answer:

1. Bhutan
2. Myanmar
3. Nepal
4. Teen Bigha Corridor
5. Bhutan
6. Palk strait

III. Consider the following statement and tick the appropriate answer

Question 1.
The Kaladan transport project by India and Myanmar consists of which of the following modes of transport?
1. Roads
2. Railways
3. Shipping
4. Inland water transport
Select the correct answer using the codes given below
(a) 1, 2 and 3 only
(b) 1,3 and 4 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Answer:
(b) 1,3 and 4 only

Question 2.
Assertion (A): India and France launched International Solar Alliance.
Reason (R): It was done to bring together countries between Tropic of Cancer and Tropic of Capricorn for co-operation of solar energy.
(a) A is correct and R is the correct explanation of A
(b) A is correct and R is not the correct explanation of A
(c) A is wrong and R is correct
(d) Both are wrong
Answer:
(a) A is correct and R is the correct explanation of A

Question 3.
Which of the following statements are true?
Statement 1: ICCR has initiated a Tagore Chair in University of Dhaka.
Statement 2: Myanmar is India’s gateway to western countries.
Statement 3: Nepal and Bhutan are land locked nations.
Statement 4: Sri Lanka is one of the partner in Nalanda University Project of India.
(a) 1,2 and 3
(b) 2, 3 and 4
(c) 1, 3 and 4
(d) 1,2 and 4
Answer:
(c) 1, 3 and 4

Question 4.
Assertion (A): OPEC has vested interest in India’s economic growth.
Reason (R): Devoid of necessary oil resources India strongly focuses on agriculture and industrial production.
(a) A is correct and R explains A
(b) A is wrong and R is correct
(c) Both are correct
(d) Both are wrong
Answer:
(c) Both are correct

IV. Match the following

A. (v)
B. (iv)
C. (ii)
D. (iii)
E. (i)

V. Give Short Answers

Question 1.
Name the neighbouring countries of India.
Answer:

• India is a vast country with Pakistan and Afghanistan to the north-west
• China, Nepal, Bhutan to the north
• Bangladesh to the east
• Myanmar to the far east
• Sri Lanka (from south-east) and Maldives (from south-west) are two countries that lie close to India separated by the Indian Ocean.

Question 2.
Write a short note on Strategic partnership Agreement (SPA).
Answer:

1. Indo – Afghan relation was strengthened by the strategic partnership , agreement.
2. SPA provide assistance to rebuild Afghan’s infrastructure, institutions, agriculture, water, education, health and providing duty – free access to the Indian market.

Question 3.
Mention the member countries of BRICS.
Answer:

• Brazil
• Russia
• India
• China
• South Africa

Question 4.
What do you know about Kaladan Multi-Model Transit Transport?
Answer:

1. India is building the kaladan multi – model transit transport, a road-river- port cargo transport project to link kolkata to Sittwe in Myanmar.
2. A project aiming to connect Kolkata with Ho chi minh city on the south sea for the formation of an economic zone will have a road pass through Myanmar, Cambodia and Vietnam and work on the first phase connecting Guwahati with Mandalay is currently underway.

Question 5.
How do you assess the importance of Chabahar agreement?
Answer:
A trilateral agreement called the Chabahar Agreement was signed between India, Afghanistan . and Iran, which has led to the establishment of transit and transport corridor among three countries using Chabahar port. This port is seen as golden gateway for India to access landlocked markets of Afghanistan and Central Asia by passing Pakistan.

Question 6.
List out any five global groupings in which India is a member.
Answer:
IBSA, BCIM, MGC, BBIN, and SCO.

Question 7.
What is the role of Japan India Institute of Manufacturing (JIM)?
Answer:
In the manufacturing sector Japan announced its co-operation of training 30,000 Indian people in the Japan India Institute of Manufacturing (JIM) providing Japanese style manufacturing skills to enhance India’s manufacturing industry base and contribute to ‘Make in India’ and ‘Skill India’ initiatives. In 2017, the first four JIMs were started in the states of Gujarat, Karnataka, Rajasthan and Tamil Nadu.

VI. Answer in detail

Question 1.
Highlight India and International organisation with special reference to any three India’s global groupings.
Answer:

1. India is a potential superpower and has a growing international influence all around the world.
2. India has is a member of formal groupings like UNO, NAM, SAARC, G20 and the commonwealth.
3. India is an activity engaged in general economic diplomacy, which is evident in the country being part of several economic coalitions, as listed in the table below.

Question 2.
Trace the reason for the formation of BRICS and write its objectives.
Answer:
Reason for the formation of BRICS To be an alternative to World Bank and IMF to challenge U.S. supremacy.
To provide self-owned and self-managed organisations to carry out developmental and economical plans in its member nations.
Objectives of BRICS

• To achieve regional development
• It acts as a bridge between developed and developing countries
• To contribute extensively to development of humanity
• To establish a more equitable and fair world
• Boost intra BRICS trade in their local currencies to increase trade cooperation and cope with the current international financial crisis.
• To promote the technological information exchange among the member states
• To enhance inclusive economic growth that will lead to an increase in the creation of jobs, fight against poverty and accelerate the economic transformation of members.

Question 3.
Mention OPEC missions and how does it help other countries?
Answer:
OPEC’S Mission:

1. To coordinate oil policies in its member countries.
2. Help stabilise oil markets.
3. To secure fair and stable income to petroleum producers.
4. An efficient, economic and regular supply of oil to consuming nations.
5. A fair return on capital to those investing in the petroleum industry.

How does OPEC help other countries?

1. The OPEC, fund for International Development (OPID) is an institution that help finance projects with low interest loans.
2. It also provides grants to social and humanitarian projects..
3. OPEC has an information centre with over 20,000 volumes including books reports, maps and conference, proceedings related to petroleum energy and the oil markets.
4. The information centre is open to the public and is often used by researchers and students.

VII. Project and Activity

Question 1.
Students can be asked to collect information from newspapers about India’s relation with world countries.
Answer:
Students should find any article from Tamil (or) English newspaper about India’s relation with world countries.

Eg: Foreign Minister’s visit to India.

[OR]

Indian Prime Minister or President’s visit to foreign countries. After finding the information, cut down the article with its date and year of publication and the name of the newspaper. A minimum of five such news articles can be collected and can be pasted in a notebook to prepare an album to submit as project to the subject teacher.

A sample news taken from the English newspaper.

Times of India
Date: Sep. 17,2019

AGARTALA: Bangladesh Information Minister Hasan Mahmud said ties between India and Bangladesh is becoming better by the day under the leadership of Narendra Modi and Sheikh Hasina.

Inaugurating a 3 – day film festival here, the Minister said Bangladesh believes in having good relations with its neighbours and films play a great role in that. The film festival will feature 20 films made on the Bangladesh Liberation war.

Question 2.
Group project involving students to prepare an album with pictures on India’s latest projects with its neighboring countries.
Answer:
India’s latest project with its neighbouring countries: The Government of India gives high importance to strengthen the friendly relations and to promote understanding with neighbouring countries. As part of this policy, the Government has undertaken several development projects with our neighbouring countries. Details of projects (a sample) is given below.

Note: Students should find and collect information (or) pictures related to the project of Gol (Government of India) with its neighbouring countries taking the sample few projects given here (or) other projects also. Students should paste the pictures in a note book underlining the project, prepare it as an album, submit to the subject teacher.

Projects

Bhutan: Projects completed in Bhutan with GOI assistance include Paro airport, Bhutan broadcasting station, major highways, and construction of Mini – Hydel projects. Penden cement plant with 300 tonnes capacity was completed in 1982 with GOI assistance.

Bangladesh: India is gifting 10 ambulances to Bangladesh.

Maldives: The 200 – bed Indira Gandhi Memorial Hospital (IGMH) was set up in Maldives in 1995 at a cost of about ₹40 crores.

Nepal: The recently completed projects include 22 bridges on the East – West Highway. Setting up of trauma – center at Bir hospital in Kathmandu.

Sri Lanka: GOI has committed US $ 7.5 million to set up an India cancer centre in Colombo.

The above mentioned are only guidelines that could help a student to find what type of projects are generally undertaken.

Samacheer Kalvi 10th Social Science India’s International Relations Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
Independent India has been consistently fostering.
(a) World peace
(b) International co-operation
(c) Both (a) and (b)
(d) None
Answer:
(c) Both (a) and (b)

Question 2.
………… development of nations can be achieved only through world peace.
(a) Economic
(b) Social
(c) Political
Answer:
(a) Economic

Question 3.
How many kilometre that Pipeline between Siliguri in West Bengal and ‘ Parbatipur (Bangladesh).
(a) 130
(b) 150
(c) 170
(d) 190
Answer:
(a) 130

Question 4.
China became republic in ……………
(a) 1947
(b) 1949
(c)1950
Answer:
(b) 1949

Question 5.
How many hydro electric projects the Government of India has constricted in Bhutan.
(a) 1
(b) 5
(c) 3
(d) 2
Answer:
(c) 3

Question 6.
…………….. is located South of Lakshadweep islands in the Indian ocean.
(a) Sri Lanka
(b) Myanmar
(c) Maldives
(d) none
Answer:
(c) Maldives

Question 7.
India’s second-largest border is shared with:
(a) Maldives
(b) Myanmar
(c) Nepal
(d) Bhutan
Answer:
(b) Myanmar

Question 8.
In …………… a 25 years treaty of friendship, co-operation and peace was signed by India and Bangladesh at …………..
(a) 1971, New Delhi
(b) 1972, Dacca
(c) 1982, Lahore
Answer:
(b) 1972, Dacca

Question 9.
The 204 – kilometre long Mahendra Raj marg to link …………….. and India
(a) Kathmandu
(b) Kalandan
(c) Sittwe
(d) none
Answer:
(a) Kathmandu

Question 10.
In which agreement India tried to bring positive change in the relationship of Pakistan.
(a) Strategic Partnership Agreement
(b) Shimla Agreement
(c) International Agreement
(d) All the above
Answer:
(b) Shimla Agreement

Question 11.
Which king had sent his son and daughter to ceylon (Sri Lanka) for the propagation of Buddhism.
(a) Chandra Gupta Mourya
(b) Ashoka
(c) Kanishka
(d) none
Answer:
(b) Ashoka

Question 12.
The cease fire line determined in ……………………….. was called the LOC.
(a) 1947
(b) 1945
(c) 1949
(d) 1943
Answer:
(c) 1949

Question 13.
……………… gives India access to advance communication technology used in U.S defence equipment.
(a) COMCASA
(b) AVSINDEX
(c) JIM
(d) MAHSR
Answer:
(a) COMCASA

Question 14.
India and France launched the international ……………… between Tropic of cancer and Tropic of capricorn.
(a) Solar Alliance
(b) Railway
(c) domestic development
(d) none
Answer:
(a) Solar Alliance

Question 15.
Which country decided to introduce the Japan’s Shikansen system.
(a) Australia
(b) India
(c) West Asia
(d) Europe
Answer:
(b) India

Question 16.
Which institute providing manufacturing skills to enhance India’s manufacturing industry (Make in India).
(a) JIM
(b) JEC
(c) MAHSR
(d) COMCASA
Answer:
(a) JIM

Question 17.
Which course was introduced in engineering colleges was established in Andhrapradesh.
(a) JIM
(b) JEC
(c) both (a) and (b)
(d) none
Answer:
(b) JEC

Question 18.
Which port is seen as golden gate way for India?
(a) Chabahar
(b) Kandla
(c) Gwadar
(d) All the above
Answer:
(a) Chabahar

Question 19.
Mention the C of the BRICS:
(a) China
(b) Vienna
(c) Japan
(d) Europe
Answer:
(a) China

Question 20.
Which economist was coined BRICS?
(a) British
(b) French
(c) German
(d) Russian
Answer:
(a) British

Question 21.
NDB gives priority to projects aimed at developing ……………… sources.
(a) Renewable
(b) Non – Renewable
(c) both (a) and (b)
(d) none
Answer:
(a) Renewable

Question 22.
The contingent Reserve Arrangement (CRA) for providing protection against ……………… pressures.
(a) liquidity
(b) currency issues
(c) both (a) and (b)
(d) Trade
Answer:
(c) both (a) and (b)

Question 23.
Which centre has cover 20,000 volumes including books, maps related to petroleum.
(a) Information centre (OPEC)
(b) Research Centre (OPEC)
(c) Universities (OPEC)
(d) All the above
Answer:
(a) Information centre (OPEC)

Question 24.
……………… is one of the biggest consumers of crude oil.
(a) Nepal
(b) China
(c) India
(d) Pakistan
Answer:
(c) India

Question 25.
India strongly focuses on production.
(a) Agriculture
(b) industrial
(c) both (a) and (b)
(d) rural
Answer:
(c) both (a) and (b)

Question 26.
India extend its support to the in all her efforts.
(a) U.N.O
(b) W. T. O
(c) world bank
(d) none
Answer:
(a) U.N.O

Question 27.
Who is an active member of BRICS.
(a) Nepal
(b) Pakistan
(c) India
(d) Bangladesh
Answer:
(c) India

Question 28.
Which bank is lending for infrastructure project?
(a) The New Development Bank
(b) Contingent Reserve Arrangement
(c) global liquidity currency
(d) none
Answer:
(a) The New Development Bank

Question 29.
How many seats per year to Indian national for a master’s degree in university of Japan.
(a) 30
(b) 20
(c) 10
(d) 5
Answer:
(b) 20

Question 30.
Who is a super power and has a growing international influence all around the world.
(a) China
(b) Japan
(c) Pakistan
(d) India
Answer:
(d) India

II. Fill in the blanks

1. ……………….. has always been known as a peace – loving country.
2. India’s position is ……………….. in its neighbourhood.
3. ……………….. is surrounded by many neighbouring countries.
4. Indo – Afghan relation was strengthened by the ………………..
5. ……………….. of Baluchistan active supporter of the Indian National congress.
6. ……………….. has built kandahar international cricket stadium.
7. India and ……………….. share 54 common rivers and a bilateral joint River commission is working to maximise benefits.
8. ……………….. has initiated a Tajore chair in university of Dhaka (Scholarship).
9. ……………….. is India’s gate way to Western countries.
10.  ……………….. one of the partner in Nalanda university project of India.
11.  ……………….. represents one of the main indicators of bilateral co-operation between India and Bhutan.
12. India declared the bilateral trade relation known as ………………..
13. China being the ……………….. of the world.
14. ……………….. is a small land locked country.
15. Nepali and Indian people visit each other’s country for religions ………………..
16. India included ……………….. in the VIII schedule of the constitution.
17. There are a number of ……………….. along Indo- Nepal border.
18. A joint hydropower project is being built on the ……………….. River.
19. The Government of India and Nepal have signed ……………….. agreements.
20. ……………….. remains our core concern in the relationship with Pakistan.
21. The cross-border firing between India and ………………..
22. ……………….. is the bone of contention between India and Pakistan.
23. ……………….. is a major irritant.
24. India and Pakistan under the ……………….. of 1972.
25. Sri Lankan investments in India include ……………….. (garment city)
26. COMCASA is valid for a period of ………………..
27. French space launch pads are used by ………………..
28. ……………….. broadens the relationship raising awareness and promoting exchanges between two countries.
29. ……………….. is one of most successful examples of Japanese co-operation.
30. JIM providing training for Indian-people in ………………..
31. Trade relations were established between civilisation of Mesopotemia and ………………..
32. ……………….. gateway to land locked and energy rich
33. In trading routes ran from ancient Sumeria to the Indus civilisation called ………………..
34. The acronym BRICS was coined by ……………….. a famous British economist.
35. ……………….. is a multilateral development Bank.
36. ……………….. are defining changes to have huge geo – economic and geo – political impact.
37. ……………….. mission to co-ordinate oil policies in its member countries.
38. ……………….. is an institution that help finance projects with low interest loans.
39. ……………….. doesn’t have enough oil reserves.
40. India – Japan join laboratories in the area of ………………..

Answers:

1. India
2. unique
3. India
4. Strategic Partnership Agreement (SPA)
5. Khan Abdul Ghaffar Khan
6. India
7. Bangladesh
8. Indian Council for Cultural Relations (ICCR)
9. Myanmar
10. Sri Lanka
11. Hydel power sector
12. Bharat to Bhutan B2B
13. Manufacturing hub
14. Nepal
15. Pilgrimage
16. Nepalese language
17. Tiger reserves
18. Sharda
19. Three-sister-city
20. Terrorism
21. Pakistan
22. Kashmir
23. Cross border terrorism
24. Shimla Agreement
25. Brandix
26. 10 years
27. ISRO
28. The Australia India council
29. Delhi metro
30. Manufacturing sector
31. The Indus valley
32. West Asia, Central Asia
33. Meluna
34. Jim O’Neill
35. NDB (New Development Bank)
36. The Contingent Reserve Arrangement (CRA)
37. OPEC 38. OPID
38. India
39. Information and communication Technology

III. Consider the following statement and tick the appropriate answer

Question 1.
Assertion (A): The Farakka accord on sharing of Ganga waters signed in 1977 is a historic agreement.
Reason (R): India and Bangladesh share 54 common rivers and a bilateral joint river commission is working to maximise benefits.
(a) A is correct and R explains A.
(b) A is wrong and R is correct
(c) Both are correct
(d) Both are wrong
Answer:
(a) A is correct and R explains A.

Question 2.
Which of the following statements are false?
Statement 1: India’s position is unique in its neighbourhood.
Statement 2: Myanmar is a land locked nations.
Statement 3: The cross border firing between India and Nepal.
Statement 4: Kashmir is the bone of contention between India and Pakistan.
(a) 1,2, and 3
(b) 2, 3 and 4
(c) 1,2 and 4
(d) 2 and 3
Answer:
(d) 2 and 3

Question 3.
Assertion (A): Maldives is located South of Lakshadweep Islands in the Indian oceans.
Reason (R): The relationship with Maldives is important for India given its strategic location and geo – graphical proximity.
(a) A is correct and R is correct explanation of A.
(b) A is correct and R is not the correct explanation of A
(c) A is wrong and R is correct
(d) Both are wrong
Answer:
(a) A is correct and R is correct explanation of A.

Question 4.
Assertion (A): McMahon line is the boundary line between India and China.
Reason (R): The secretary of state for India (in British cabinet) Arthur Henry McMahon represented British India at the conference.
(a) A is correct and explains A
(b) A is wrong and R is correct
(c) Both A and R are correct
(d) A is correct and R is wrong.
Answer:
(c) Both A and R are correct

IV. Match the following

Question 1.

Match the Column I with Column II.
Answer:
A. (iv)
B. (v)
C. (i)
D. (iii)
E. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

Question 3.
Match the Column I with Column II.

Answer:
A. (v)
B. (iii)
C. (iv)
D. (ii)
E. (i)

Question 4.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (ii)
D. (v)
E. (i)

Question 5.
Match the Column I with Column II.

Answer:
A. (v)
B. (iii)
C. (i)
D. (ii)
E. (iv)

V. Give Short Answer

Question 1.
What is the role of India as a Great Helper?
Answer:
India is basically against colonization and wants to see all the countries of the world free from foreign domination. It played a great role in freeing Indonesia from the domination of Holland. In the same way, it has supported the freedom movements started by Egypt, Sudan, Indo-China, Ghana, Morocco and Bangladesh.

Question 2.
Name the formal groups in which India is a member.
Answer:
India is a member of formal groupings like U.N.O, NAM, SAARC, G-20 and the common wealth.

Question 3.
Explain India’s relationship with Pakistan.
Answer:
Inspite of part conflicts both India and Pakistan are trying to come closer. The Delhi-Lahore bus service was launched on March 10th 1999 to bring the people of the two countries closer. Negotiations for setting up Iran-Pakistan-India gas pipeline are taking place.

Question 4.
Mention the India’s relationship with OPEC.
Answer:

1. India is one of the biggest consumers of crude oil.
2. OPEC obviously has vested interest in India’s economic growth.
3. We import 86% of crude oil, 70% natural gas, 35% of cooking gas from OPEC countries.
4. India has been identified as a greater partner for OPEC mainly because of its high oil demand.

Question 5.
‘The relationship between India and Sri Lanka is smooth’-Justify.
Answer:
Sri Lanka is a Buddist country. The Mauryan emperor Ashoka spread Buddism there by sending his son and daughter. We have good trade relation with Sri Lanka India always support Sri Lanka on just and reasonable grounds. Thus the relationship between India and Sri Lanka is very smooth. It will be continued forever.

Question 6.
Write about Khan Abdual Ghaffar Khan.
Answer:
Khan Abdul Ghaffar Khan of Baluchistan (a border province in 10 day’s Pakistan) was a prominent leader of the Indian independence movement and active supporter of the Indian national congress.

Question 7.
Why Buddhist saint went to Bhutan from India?
Answer:
Gur Padmasambhava, a Buddhist saint who want to Bhutan from India, played an influential role in spreading Buddhism and Cementing traditional ties between people of both nations.

Question 8.
List out the Indian states have their boundary with Nepal.
Answer:
Sikkim, west Bengal, Bihar, Uttarpradesh and Uttarakhand.

Question 9.
In what way JIM providing training to Indian people?
Answer:
The Japan India Institute of manufacturing(JIM) providing Japanese style manufacturing skills to enhance India’s manufacturing industry base and contribute to “Make in India” and “skill India” initiatives.

Question 10.
Write a short note on a joint hydro power project.
Answer:

1. A joint hydropower project is being built on the Sharda river.
2. This power plant helps both India and Nepal with respect to electricity production and irrigation facilities.

VI. Answer in detail

Question 1.
Explain the relationship of India with her neighbouring countries.
Answer:
India and Pakistan:
Insipite of port conflicts both India and Pakistan are trying to come closer. The Delhi-Lahore bus service was launched on March 16^th 1999 to bring the people of the two countries closer. Negotiations for setting up Iran-Pakistan-India gas pipeline are taking place.

India and China:
When China became republic in 1949, India was the first country to recognize it. Both the countries have successfully attempted to restore the economic lines. China has formally declared that she will back India’s claim for becoming a permenent member of United Nation’s Security Council.

India and Srilanka:
Srilanka is a Buddhist country. The Mauryan emperor Ashoka spread Buddhism there by sending his son and daughter. We have good trade relation with Srilanka. India always support Srilanka on just and reasonable grounds. Thus the relationship between India and Srilanka is very smooth. It will be continued for ever.

India and Bangladesh:
It is due to the effort and support of Smt. Indira Gandhi, the Prime Minister of India, Bangladesh got freedom from Pakistan in 1971. In 1972, a 25 years treaty of friendship, co operation and peace was signed in Dacca by India and Bangladesh. The farakka Barrage issue regarding the distribution of Ganga water was settled amicably. Thus India is a very good friend of Bangladesh. Our friendship with Bangladesh will go on forever.

Question 2.
Write about India and Pakistan relationship?
Answer:

1. Since the bifurcation of territory which demarcated India and Pakistan in 1947.
2. The two nations have had strained relations due to disagreements over a number of key issues.
3. Terrorism remains our core concern in the relationship with Pakistan.
4. But India has made extreme efforts to improve and stabilise relations with Pakistan.
5. The cross – border firing between India and Pakistan and the terrorist attacks combined have taken its toll on the Kashmiri’s who have suffered poor living standards and an erosion of human rights.
6. Kashmir is the bone of contention between India and Pakistan, which has brought the two countries into open clash many times.
7. Cross-border-terrorism is a major irritant.
8. India tried bring a positive change in the relationship of the two countries through bilateral agreements such as Shimla Agreement and Lahore Declaration.

Students can download 10th Science Chapter 13 Structural Organisation of Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 13 Structural Organisation of Animals

Samacheer Kalvi 10th Science Structural Organisation of Animals Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
In leech locomotion is performed by:
(a) Anterior sucker
(b) Posterior sucker
(c) Setae
(d) None of the above
Answer:
(a) Anterior sucker

Question 2.
The segments of leech are known as _____.
(a) Metameres (somites)
(b) Proglottids
(c) Strobila
(d) All the above.
Answer:
(a) Metameres (somites).

Question 3.
Pharyngeal ganglion in leech is a part of:
(a) Excretory system
(b) Nervous system
(c) Reproductive system
(d) Respiratory system
Answer:
(b) Nervous system

Question 4.
The brain of leech lies above, the _____.
(a) Mouth
(b) Buccal Cavity
(c) Pharynx
(d) Crop.
Answer:
(c) Pharynx

Question 5.
The body of leech has:
(a) 23 segments
(b) 33 segments
(c) 38 segments
(d) 30 segments
Answer:
(b) 33 segments

Question 6.
Mammals are animals.
(a) Cold blooded
(b) Warm blooded
(c) Poikilothermic
(d) All the above
Answer:
(b) Warm blooded

Question 7.
The animals which give birth to young ones are _____.
(a) Oviparous
(b) Viviparous
(c) Ovoviviparous
(d) All the above.
Answer:
(d) All the above

II. Fill in the blanks:

1. The posterior sucker is formed by the fusion of the ………. segments.
2. The existence of two sets of teeth in the life of an animal is called ……….. dentition.
3. The anterior end of leech has a lobe-like structure called ………..
4. The blood sucking habit of leech is known as ………..
5. ………. separate nitrogenous waste from the blood in rabbit.
6. ……… spinal nerves are present in rabbit.

Answer:

1. last seven
2. diphyodont
3. anterior sucker
4. sanguivorous
5. Nephrons (kidney)
6. 37 pair

III. Identify whether the statements are True or False. Correct the false statement:

1. An anticoagulant present in saliva of leech is called heparin.
2. The vas deferens serves to transport the ovum.
3. The rabbit has a third eyelid called tympanic membrane which is movable.
4. Diastema is a gap between premolar and molar teeth in rabbit.
5. The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora quadrigemina.

Answer:

1. True
2. False – Vas deferens serves to transport the sperm.
3. True
4. False – The gap between the incisors and premolars.
5. False – The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora corpus callosum.

IV. Match columns I, II and III correctly:

Answer:

V. Answer in a sentence:

Question 1.
Give the common name of the Hirudinaria granulosa.
Answer:
The common name of Hirundinaria granulosa is Indian Cattle Leech.

Question 2.
How does leech respire?
Answer:
Leech respire through the skin.

Question 3.
Write the dental formula of rabbit.
Answer:
The dental formula of rabbit is \(\frac{2033}{1023}\)

Question 4.
How many pairs of testes are present in leech?
Answer:
There are 11 pairs of testes are present in Leech.

Question 5.
How is diastema formed in rabbit?
Answer:
Diastema is due to the absence of canine. It is a gap between incisors and premolars in the upper jaw and lower jaw.

Question 6.
What organs are attached to the two bronchi?
Answer:
The organs attached to the two bronchi are lungs.

Question 7.
Which organ acts as a suction pump in leech?
Answer:
The Pharynx acts as a suction pump in Leech.

Question 8.
What does CNS stand for?
Answer:
The full form of CNS is Central Nervous System.

Question 9.
Why is the teeth of rabbit called heterodont?
Answer:
The dentition of rabbit is called heterodont, as they have different types of teeth (Incisors, premolars and molars).

Question 10.
How does leech suck blood from the host?
Answer:
The Anterior sucker helps in feeding, while both the suckers, help in attachment and locomotion.

VI. Short answer questions:

Question 1.
Why are the rings of cartilages found in trachea of rabbit?
Answer:
The wall of larynx which serves as the voice box is supported by 4 cartilaginous plates. When the air passes the vocal cord, it vibrates resulting in sound production.

Question 2.
List out the parasitic adaptations in the leech.
Answer:
Leeches lead a parasitic mode of life, by sucking the blood of vertebrates. The adaptations are

• Blood is sucked by the pharynx.
• Anterior and Posterior Suckers are provided, by which the animal attaches itself to the body of the host.
• The three Jaws, inside the mouth, causes a painless Y – shaped wound in the skin of the host,
• The salivary glands produce Hirudin, which does not allow the blood to coagulate. So, the continuous supply of blood is maintained.
• Parapodia and Setae are absent.
• Blood is stored in the crop. It gives nourishment to the leech for several months. So there is no elaborate secretion of the digestive juices and enzymes.

VII. Long answer questions:

Question 1.
How is the circulatory system designed in leech to compensate the heart structure?
Answer:
The circulation in Leech is Haemocoelic system. There are no true blood vessels. The blood vessels are replaced by channels called Haemocoelic channels or canals, filled with blood like a fluid. The coelomic fluid contains Haemoglobin.

There are four longitudinal channels. One channel lies above (dorsal) to the Alimentary canal, one below (ventral) to the Alimentary canal. The other two channels lie on either (lateral) side of the Alimentary canal, which serves as a heart and have inner valves. All the four channels are connected together posteriorly in the 26th segment. Thus the circulatory system is designed in Leech to compensate the heart structure.

Question 2.
How does locomotion take place in leech?
Answer:

1. Looping or Crawling movement : Looping movement is brought about by the contraction and relaxation of muscles. The two suckers serve for attachment during movement. The animal fixes its posterior sucker on the substratum.
2. Swimming movement : The animal swims in the water by undulating movements of the body.

Question 3.
Explain the male reproductive system of rabbit with a labelled diagram.
Answer:
The male rabbit has a pair of testes. They are oval in shape. They are kept in two sacs called scrotal sacs hanging down from the abdomen. Each testes is formed of numerous fine tubules called seminiferous tubules. A coiled tubule called epididymis is formed at the end of seminiferous tubules. Epididymis lead into the sperm duct called vas deferens. The vas deferens run forward and enters abdominal cavity through urinary bladder. The urethra runs back and passes into the penis. There are three accessory glands associated with the male reproductive system. They are prostate glands, cowper’s gland and perineal glands. Their secretion nourishes and activates the reproduction.

VIII. Higher Order Thinking Skills (HOTS).

Question 1.
Arjun is studying in the tenth standard. He was down with fever and went to meet the doctor. As he went to the clinic he saw a patient undergoing treatment for severe leech bite. Being curious, Arjun asked the doctor why leech bite was not felt as soon as it attaches to the skin? What would have been the reply given by the doctor?
Answer:
The doctors would have replied that the leeches inject an anaesthetic substance, that prevents the host from feeling their bite.

Question 2.
Shylesh has some pet animals at his home. He has few rabbits too, one day while feeding them he observed something different with the teeth. He asked his grandfather, why is it so? What would have been the explanation of his grandfather?
Answer:
The rabbit has three types of teeth – Incisors are front teeth used for cutting, premolar and molar are used for grinding. Canine is absent as rabbit are herbivores. The gap between the incisor and premolar is called diastema. It helps in mastication and chewing of food in herbivores animal.

IX. Value-Based Questions:

Question 1.
Leeches do not have an elaborate secretion of digestive juices and enzymes. Why?
Answer:
The digestion in leeches in very slow. So, the blood stored in the crop gives nourishment to the leech for several months. So there is not elaborate secretion of digestive juices and enzymes.

Question 2.
How is the digestive system of rabbit suited for herbivorous mode of feeding?
Answer:
Rabbit are herbivores which feed on plants. The plant contain cellulose which need cellulose to digest. The laccum of Rabbit contain large number of symbiotic bacteria that helps in digestion of cellulose.

Samacheer Kalvi 10th Science Structural Organisation of Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
(a) Vas deferens and Epididymis
(b) Ovary and Caeca
(c) Hirudin and Stomach
(d) Nephridia and Papillae.
Answer:
(a) Vas deferens and Epididymis

Question 2.
Diastema is:
(a) A part of pelvic girdle in rabbit
(b) A type of tooth in rabbit
(c) Space in teeth line in mammals
(d) Structure in eye of rabbit
Answer:
(c) Space in teeth line in mammals

Question 3.
(a) Suckers and Mammary glands
(b) Cowper’s gland and Perineal gland
(c) Forebrain and Oesophagus
(d) Cellulose and Colouration.
Answer:
(b) Cowper’s gland and Perineal gland

Question 4.
If the dental formula of rabbit is \(\frac{2023}{1023}\) What does it show?
(a) Total number of teeth in Rabbit is 15
(b) Number of total incisors in Rabbit is 3
(c) Diastema is present between incisors and premolars
(d) In the formula 2033 is for adult and 1023 is for young ones
Answer:
(c) Diastema is present between incisors and premolars

Question 5.
Number of pairs of salivary glands present in Rabbit is:
(a) one
(b) three
(c) four
(d) five
Answer:
(c) four

Question 6.
Number of Vertebrae in rabbit is:
(a) 44 – 47
(b) 40 – 44
(c) 42 – 48
(d) 47 – 50
Answer:
(a) 44 – 47

Question 7.
If the diaphragm of a rabbit is perforated breathing is:
(a) Not affected
(b) Increased
(c) Decreased
(d) Stopped
Answer:
(d) Stopped

Question 8.
Tracheal rings in rabbit are:
(a) complete
(b) dorsally incomplete
(c) lateral incomplete
(d) incomplete
Answer:
(b) dorsally incomplete

Question 9.
Which one of the following is not a characteristic of leech?
(a) closed circulatory system
(b) segmentation
(c) pseudo coelom
(d) ventral nerve cord
Answer:
(c) pseudo coelom

Question 10.
The blood vascular system, of rabbit is:
(a) open type
(b) closed type
(c) semi closed type
(d) semi open type
Answer:
(b) closed type

Question 11.
The wall of Rabbit’s heart is thick due to the presence of:
(a) Inner layer endocardium
(b) Middle layer myocardium
(c) Outer layer pericardium
(d) Outer layer epicardium
Answer:
(b) Middle layer myocardium

Question 12.
Leech belongs to the class:
(a) polychaeta
(b) oligochaeta
(c) hirundinea
(d) archiannelida
Answer:
(c) hirundinea

Question 13.
A temporary clitellum occur during the breeding season in:
(a) Pheretima
(b) Heteroneris
(c) Hirundinaria
(d) Aphrodile
Answer:
(c) Hirundinaria

Question 14.
Saliva of leeches contains an anti coagulation called:
(a) Heparin
(b) Histamine
(c) Hirudin
(d) Haematin
Answer:
(c) Hirudin

II. Fill in the blanks:

1. Hirudinaria granulosa belong to the phylum ……..
2. The scientific name of the rabbit is ………
3. ………. is the segmentation of the body.
4. The type of movement is brought by the contraction and relaxation of muscles in leeches is ………
5. In leech, the digestion takes place in stomach by the action of …………
6. The ……….. prevents the entry of food into the trachea through the glottis.
7. The existence of two sets of teeth in the life of an animal is called ………… dentition.
8. ……….. contains bacteria that helps in digestion of cellulose.
9. The anterior part of the oviduct in rabbit is …………
10. Breathing movement in mammals are brought by ………..
Answer:
1. Annelida
2. Oryctolagus cuniculus
3. Metamerism
4. Looping or crawling movement
5. Proteolytic enzyme
6. Epiglottis
7. Diphyodont
8. Caecum
9. Fallopian tube
10. Diaphragm

III. Identify whether the statements are True or False. Correct the false statement:

1. Mammary gland in male is the most striking feature of mammals.
2. The leech makes a triradiate or y-shaped incision in the skin of the host by the joins protrude through the mouth.
3. Crop and its diverticular in leech can store large amount of blood which can be slowly digested.
4. Breathing movement in Rabbit are brought by the movement of vibrissae.
5. In rabbit pair of cowper’s gland and perineal gland are present only in the male.

Answer:

1. False – Mammary gland in female is the most striking feature of mammals.
2. True
3. True
4. False – Breathing movement in Rabbit are brought by Diaphragm
5. False – In rabbit pair of cowper’s gland and perineal gland are present both male and female

IV. Match the following:

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

V. Answer in a sentence:

Question 1.
Name the excretory organ of leech.
Answer:
Excretion in leech takes place by nephridia.

Question 2.
Give the Scientific name of Rabbit.
Answer:
Oryctolagus Cuniculus.

Question 3.
Where is the brain of rabbit located?
Answer:
The brain of rabbit is located in the cranial cavity and covered by three membrane of duramater, piamater and arachnoid membrane.

Question 4.
How many pairs of cranial nerves are there in the Peripheral Nervous System?
Answer:
12 pairs of cranial nerves.

Question 5.
What is other name of whiskers in rabbit?
Answer:
The sides of the upper lip produce stiff long thick hairs called vibrissae or whisker which are tactile sensory organ.

Question 6.
Which type of rabbit are endangered species?
Answer:
Pygmy Rabbits are listed as an endangered species.

Question 7.
Name the existence of two sets of teeth in the life of an animal.
Answer:
Diphyodont dentition

Question 8.
Why Rabbits are called gregarious animals?
Answer:
Rabbits are called gregarious animals as they move in group.

Question 9.
Which animals are called sanguivorous?
Answer:
Blood sucking animals.

Question 10.
What are nephridropores?
Answer:
In leech, excretion takes place by segmentally arranged paired tubules called nephridia. There are 17 pairs of nephridia which open by nephridiopores from 6th to 22nd segment.

VI. Short Answer Questions:

Question 1.
Write the systematic position of Indian Cattle Leech.
Answer:

Question 2.
What do you know about the Trunk of Rabbit?
Answer:
The trunk is divisible into an anterior thorax and a posterior abdomen. In females, four or five teats or nipples are present on the ventral surface between Thorax and abdomen. The trunk has two pairs of Pentadactyl limbs. The forelimbs are shorter than the hind limbs.

All the digits bear claws. The anus is present at the posterior end. In females, on the ventral side, a slit-like Vulva is present. In males, the Penis is present in the ventral side of Anus. The male has a pair of testes, enclosed by Scrotal Sacs.

Question 3.
How do the leeches respire?
Answer:
There is no special respiration organ in leech. The skin serves as a respiratory i organ. The capillaries containing the haemocoelomic fluid extend in between the cells of the epidermis, acts as a permeable membrane through which the exchange of gases takes place by diffusion.

Question 4.
What are diphyodont dentition and Heterodont dentition?
Answer:
The existence of two sets of teeth in the life of an animal is called diphyodont dentition. The two types of teeth are Milk teeth (Young ones) and Permanent teeth (in adults).

The different types of dentition are called Heterodont. There are four kinds of teeth in mammals.
The incisors (I), Canines (C), Premolars (PM) and Molars (M).

Question 5.
List out the five layers of body wall of Leech.
Answer:
The body wall of leech consists of five layers.

1. Cuticle
2. Epidermis
3. Dermis
4. Muscular layer and
5. Botryoidal tissue

Question 6.
Give the systematic position of Rabbit.
Answer:

Question 7.
Explain the Respiratory system of Leech.
Answer:
Respiration takes place through the skin in Leech. Dense, network to tiny blood vessels called Capillaries, containing haemocoel fluid extend, in between the cells of the epidermis. The exchange of respiratory gases takes place by diffusion. Oxygen dissolved in water diffuses through the skin, into haemocoel fluid, while Carbon dioxide, diffuses out. The skin is kept moist and slimy, due to the secretion of mucus, which prevents the skin from drying.

Question 8.
List out the steps involved in Inspiration in Rabbit.
Answer:
During Inspiration the atmospheric air takes the following route.

VII. Long answer questions:

Question 1.
Compare the digestive system of Leech and Rabbit.
Answer:

Question 2.
Short notes on the Nervous System of Leech.
Answer:
The Central Nervous System of Leech consists of a nerve ring and a paired ventral nerve cord. The nerve ring surrounds the Pharynx and is formed of Suprapharyngeal ganglion (brain), Circum pharyngeal connective and Subpharyngeal ganglion. The Subpharyngeal ganglion lies below the Pharynx and is formed by the fusion of four pairs of Ganglia.

Students can download 6th Science Term 2 Chapter 1 Heat Questions and Answers, Notes, Samacheer Kalvi 6th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 6th Science Solutions Term 2 Chapter 1 Heat

Samacheer Kalvi 6th Science Heat Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
When an object is heated, the molecules that make up the object
(a) begin to move faster
(b) lose energy
(c) become heavier
(d) become lighter
Answer:
(a) begin to move faster

Question 2.
The unit of heat is
(a) newton
(b) joule
(c) volt
(d) Celsius
Answer:
(b) joule

Question 3.
One litre of water at 30°C is mixed with one litre of water at 50°C. The temperature of the mixture will be
(a) 80°C
(b) More than 50°C but less than 80°C
(c) 20°C
(d) around 40°C
Answer:
(d) around 40° C

Question 4.
An iron ball at 50°C is dropped in a mug containing water at 50°C. The heat will
(a) flow from iron ball to water.
(b) not flow from iron ball to water or from water to iron ball.
(c) flow from water to iron ball.
(d) increase the temperature of both.
Answer:
(b) not flow from iron ball to water or from water to iron ball.

II. Fill in the Blanks

1. Heat flows from a ……….. body to a ………… body.
2. The hotness of the object is determined by its ………..
3. The SI unit of temperature is …………
4. Solids ……….. on heating and ………… on cooling.
5. Two bodies are said to be in the state of thermal ………… if there is no transfer of heat taking place.

Answer:

1. hot, cold
2. temperature
3. Kelvin
4. expand, contract
5. equilibrium

III. True or False. If False, give the correct answer.

1. Heat is a kind of energy that flows from a hot body to a cold body.
2. Steam is formed when heat is released from water.
3. Thermal expansion is always a nuisance.
4. Borosilicate glass do not expand much on being heated.
5. The unit of heat and temperature are the same.

Answer:

1. True
2. False – Steam is formed when the heat is absorbed from the water.
3. False – Thermal expansion is always not a nuisance.
4. True
5. False – Unit of heat and temperature are different.

IV. Give reasons for the following

Question 1.
An ordinary glass bottle cracks when boiling water is poured into it, but a borosilicate glass bottle does not.
Answer:
The reason is that the borosilicate glass does not expand much on being heated and therefore they do not crack.

Question 2.
The electric wire which sag in summer become straight in winter.
Answer:

1. During summer thermal expansion takes place in electric wire.
2. In winter it contracts so it becomes straight.

Question 3.
Rivet is heated before fixing in the hole to join two metal plates.
Answer:

1. When we heat rivet expansion takes place and becomes soft.
2. One end of the rivet is hammered to form a new head.
3. When cooled, the rivet will contract and hold tightly.

V. Match the following

Answer:
1. – e
2. – c
3. – d
4. – a
5. – b

VI. Analogy

1. Heat: Joule :: Temperature : ………
2. Ice cube : 0°C :: Boiling water : ………..
3. Total Kinetic Energy of molecules: Heat:: Average Kinetic Energy : …………….

Answer:

1. Kelvin
2. 100° C
3. Temperature

VII. Give Very Short Answer:

Question 1.
Make a list of electrical types of equipment at home from which we get heat.
Answer:
Water heater, Iron box, Electric kettle, Micro oven.

Question 2.
What is the temperature?
Answer:
The measurement of the warmness or coldness of a substance is known as its temperature.

Question 3.
What is thermal expansion?
Answer:
The expansion of a substance on heating is called thermal expansion.

Question 4.
What do you understand by thermal equilibrium?
Answer:
When two objects in thermal contact, no longer affect each other’s temperature, there exists Thermal equilibrium.

VIII. Give Short Answer:

Question 1.
What difference do you think heating the solid will make in their molecules?
Answer:

1. When we heat solids the vibrations and movement of molecules will increase.
2. The temperature of the object increases.
3. The distance between molecules will increase.

Question 2.
Distinguish between heat and temperature.
Answer:

IX. Answer in detail:

Question 1.
Explain thermal expansion with suitable examples.
Answer:
Thermal expansion: The expansion of a substance on heating is called, the thermal expansion of that substance.

Fitting the iron rim on the wooden wheel:

1. The diameter of the iron ring is slightly less than that of the wooden wheel.
2. So, it cannot be easily slipped on from the rim of a wooden wheel.
3. The iron ring is, therefore, first heated to a higher temperature so that it expands in size and the hot ring is then easily slipped over to the rim of the wooden wheel.
4. Coldwater is now poured on the iron ring so that it contracts in size and holds the wooden wheel tightly.

Rivetting:

1. Rivets are used to join two steel plates together.
2. Hot rivet is driven through the hole in the plates.
3. One end of the rivet is hammered to form a new rivet head.
4. When cooled, the rivet will contract and hold the two plates tightly together.

Cracking of a thick glass tumbler:

1. Glass is a poor conductor of heat.
2. When hot liquid is poured into the tumbler, the inner surface of the tumbler becomes hot and expands while the outer surface remains at room temperature and does not expand.
3. Due to this unequal expansion, the tumbler cracks.

X. Questions based on Higher Order Thinking Skills

Question 1.
When a window is accidentally left open on a winter night, will you feel uncomfortable because the cold is getting in, or because the heat is escaping from the room?
Answer:

1. When a window is left open on a winter night I will feel uncomfortable because the heat is escaping from the room.
2. The heat will transfer from high temperature to low temperature.
3. During winter cold air enters the room, so room temperature will decrease.

Question 2.
Suppose your normal body temperature was lower than what it is. How would the sensation of hot and cold change?
Answer:

1. When our body temperature is lower than normal temperature, We feel hot from the surrounding.
2. Because the surrounding temperature will be high compare to our body.

Question 3.
If you heat a circular disk with a hole, what change do you expect in the diameter of the hole? Remember that the effect of heating increases the separation between any pair of particles.
Answer:
Many of us “expect” that the diameter of the hole will decrease because the circular disk is free to expand in all directions as well. Note that expansion of metal due to heating is not like gas spreading out wherever space is available. The correct way to think about it is as follows: Hole size is irrelevant in this case. So we can think that hole is very large.

If we carve a hole so large that its radius is slightly less than that of the circular disk itself, then we will have a ring. It is obvious that the radius of the ring will increase, as atoms have more energy so their oscillation amplitude will increase. As the diameter of the ring increases, the diameter of the hole will also increase.

For example, if you want to insert one hallow pipe inside another hollow pipe of the same diameter, just heat anyone and insert the second one into the heated pipe. This explains the answer in an easy way. So it says that diameter will increase with increasing temperature.

Samacheer Kalvi 6th Science Heat Additional Important Questions and Answers

I. Choose the right answer:

Question 1.
When an electric current is passing through the conductor …………… energy is produced.
(a) Electric
(b) Heat
(c) Chemical
(d) Kinetic energy
Answer:
(b) Heat

Question 2.
One day in 1922, the air temperature was measured at 59°C in the shade in Libya ________
(a) America
(b) Africa
(c) Antarctica
(d) Europe
Answer:
(b) Africa

Question 3.
The temperature of boiling water is …………..
(a) 0° C
(b) 32° C
(c) 100° C
(d) 110° C
Answer:
(c) 100°C

Question 4.
The temperature determines the direction flow of _______
(a) heat energy
(b) kinetic energy
(c) potential energy
(d) light energy
Answer:
(a) heat energy

Question 5.
When we cool the liquid it will become …………..
(a) Gas
(b) Solid
(c) Vapour
(d) None
Answer:
(b) Solid

II. Say True or False.

1. Heat is measured in Celsius or centigrade.
2. Temperature in the form of energy.
3. The normal temperature of our body is 37°C.
4. Two objects are said to be in thermal contact if they can exchange heat energy.
5. When the vibrations move from one molecule to another molecule heat will flow.

Answer:

1. False
2. False
3. True
4. True
5. True

III. Match the Following:

Answer
1. – iv
2. – i
3. – ii
4. – v
5. – iii

IV. Analogy

1. Summer : Sag :: Winter : …………
2. Evaporation : 100°C :: Freezing : …………

Answer:

1. contract
2. 0°C

V. Give reasons for the following:

Question 1.
Gaps are left in between rails while laying a railway track.
Answer:
Reason: During summer thermal expansion takes place.

Question 2.
Hot metal ball of 80° C is dipped into water of 80°C. The ball will not contract.
Answer:
Reason: Both are in same temperature.

VI. Very Short Answer:

Question 1.
What are the sources of heat?
Answer:

1. The main source of heat is Sun.
2. Other sources are combustion, friction and electricity.

Question 2.
Define – heat.
Answer:
Heat is an energy that raises the temperature of a thing by causing the molecules in that thing to move faster.

Question 3.
How will you identify two objects are said to be in thermal equilibrium?
Answer:
Two objects in thermal contact have same temperature they are said to be in thermal equilibrium.

Question 4.
What are the measuring unit of temperature?
Answer:
SI unit of temperature is kelvin. Celsius and Fahrenheit are the other units used.

Question 5.
What will determine the direction of flow of heat from one object to another?
Answer:
Temperature will determine the direction of the flow of heat.

VII. Long Answer Questions:

Question 1.
Explain linear expansion with an experiment.
Answer:

1. The expansion in length is called linear expansion.
2. Take a bulb, dry cell, candle, cycle spoke, coin, and two wooden boxes.
3. Place one end of the cycle spoke on a wooden block and connect an electric wire to it. Put a stone over the spoke to hold it.
4. The other one of the cycle spoke is placed on another wooden block.
5. Wrap some electric wire around the coin and place it on the block. Put a stone over the coin to hold it in place.
6. Connect bulb and dry cell to the free ends of wires connected to the coin and the spoke and make the circuit.
7. When we heat the cycle spoke with a candle the length will expand and touches the coin.
8. So the circuit completes, the bulb will glow.
9. When we cool the spoke it contracts and does not touch the coin. So the circuit will disconnect, the bulb will not glow.

Students can download 10th Science Chapter 10 Types of Chemical Reactions Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 10 Types of Chemical Reactions

Samacheer Kalvi 10th Science Types of Chemical Reactions Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1
H_2(g) + Cl_29(g) → 2HCl_(g)
(a) Decomposition Reaction
(b) Combination Reaction
(c) Single Displacement Reaction
(d) Double Displacement Reaction
Answer:
(a) Decomposition Reaction

Question 2.
Photolysis is a decomposition reaction caused by ______.
(a) heat
(b) electricity
(c) light
(d) mechanical energy
Answer:.
(c) light
Hint:
\(2 \mathrm{AgBr}_{(\mathrm{s})} \stackrel{\mathrm{Light}}{\longrightarrow} 2 \mathrm{Ag}_{(\mathrm{s})}+\mathrm{Br}_{2(\mathrm{g})}\)

Question 3.
A reaction between carbon and oxygen is represented by C_(s) + O_2(g) → CO_2(g) + Heat. In which of the type(s), the above reaction can be classified?
(i) Combination Reaction
(ii) Combustion Reaction
(iii) Decomposition Reaction
(iv) Irreversible Reaction
(a) (i) and (ii)
(b) (i) and (iv)
(c) (i), (ii) and (iii)
(d) (i), (ii) and (iv)
Answer:
(d) (i), (ii) and (iv)

Question 4.
The chemical equation \(\mathrm{Na}_{2} \mathrm{SO}_{4(\mathrm{aq})}+\mathrm{BaCl}_{2(\mathrm{aq})} \rightarrow \mathrm{BaSO}_{4(\mathrm{s})} \downarrow+2 \mathrm{NaCl}_{(\mathrm{aq})}\) represents which of the following types of reaction?
(a) Neutralisation
(b) Combustion
(c) Precipitation
(d) Single displacement.
Answer:
(c) Precipitation
Hint: This reaction involves the precipitation of white BaSO₄ by mixing of Na₂SO₄ (aq) and BaCl₂ (aq). Hence it belongs to precipitation reaction.

Question 5.
Which of the following statements are correct about a chemical equilibrium?
(i) It is dynamic in nature
(ii) The rate of the forward and backward reactions are equal at equilibrium
(iii) Irreversible reactions do not attain chemical equilibrium
(iv) The concentration of reactants and products may be different
(a) (i), (ii) and (iii)
(b) (i), (ii) and (iv)
(c) (ii), (iii) and (iv)
(d) (i), (iii) and (iv)
Answer:
(a) (i), (ii) and (iii)

Question 6.
A single displacement reaction is represented by \(\mathrm{X}_{(\mathrm{s})}+2 \mathrm{HCl}_{(\mathrm{aq})} \rightarrow \mathrm{XCl}_{2(\mathrm{aq})}+\mathrm{H}_{2(\mathrm{g})}\). the following(s) could be X?
(i) Zn
(ii) Ag
(iii) Cu
(iv) Mg.
Choose the best pair.
(a) i and ii
(b) ii and iii
(c) iii and iv
(d) i and iv.
Answer:
(d) i and iv.
Hint:
Zn + 2HCl → ZnCl₂ + H₂
Mg + 2HCl → MgCl₂ + H_2.

Question 7.
Which of the following is not an “element + element → compound” type reaction?
(a) C_(s) + O_2(g) → CO_2(g)
(b) 2K_(s) + Br_2(l) → 2KBr_(s)
(c) 2CO_(g) + O_2(g) → 2CO_2(g)
(d) 4Fe_(s) + 3O_2(g) → 2Fe₂O_3(s)
Answer:
(c) 2CO_(g) + O_2(g) → 2CO_2(g)

Question 8.
Which of the following represents a precipitation reaction?
(a) A_(s) + B_(s) → C_(s) + D_(s)
(b) A_(s) + B_(aq) → C_(aq) + D_(l)
(c) A_(aq) + B_(aq) → C_(s) + D_(aq)
(d) A_(aq) + B_(s) → C_(aq) + D_(l)
Answer:
(c) A_(aq) + B_(aq) → C_(s) + D_(aq)

Question 9.
The pH of a solution is 3. Its [OH^–] concentration is ______.
(a) 1 × 10^-3 M
(b) 3 M
(c) 1 × 10^-11 M
(d) 11 M.
Answer:
(c) 1 × 10^-11 M
Hint: pH = 3
It means [H⁺] = 10^-3
[H⁺] [OH^–] = 10^-14
[10^-3] [OH^–] = 10^-14
[OH^–] = 10^-11

Question 10.
Powdered CaCO₃ reacts more rapidly than flaky CaCO₃ because of :
(a) large surface area
(b) high pressure
(c) high concentration
(d) high temperature
Answer:
(a) large surface area

II. Fill in the blanks:

1. A reaction between an acid and a base is called ………..
2. When zinc metal is placed in hydrochloric acid, ………. gas is evolved.
3. The equilibrium attained during the meiting of ice is known as ………..
4. The pH of a fruit juice is 5.6. If you add slaked lime to this juice, its pH ……….
5. The value of ionic product of water at 25 °C is ………..
6. The normal pH of human blood is …………
7. Electrolysis is type of ……….. reaction.
8. The number of products formed in a synthesis reaction is ………..
9. Chemical volcano is an example for ……….. type of reaction.
10. The ion formed by dissolution of H⁺ in water is called …………
Answer:
1. neutralization
2. H₂
3. physical equilibrium
4. increases to ‘7’
5. 1 × 10^-14 mol² dm^-6
6. 7.4
7. decomposition
8. 1
9. decomposition
10. hydronium ion

III. Match the following:

Question 1.
Identify the types of reaction:

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

IV. True or False: (If false give the correct statement)

1. Silver metal can replace hydrogen gas from nitric acid.
2. The pH of rain water containing dissolved gases like SO₃, CO₂, NO₂ will be less than 7.
3. At the equilibrium of a reversible reaction, the concentration of the reactants and the products will be equal.
4. Periodical removal of one of the products of a reversible reaction increases the yield.
5. On dipping a pH paper in a solution, it turns into yellow. Then the solution is basic.

Answer:

1. False – Silver cannot displace H₂ from HNO₃ acid, since it is placed below hydrogen in the activity series.
2. True
3. False – At equilibrium the concentration of the reactants and products do not change it remains constant, but the concentration of the reactants and the products will not be equal.
4. True
5. False – The solution is neutral if the solution is basic it will be green in colour.

V. Short answer questions:

Question 1.
When an aqueous solution of potassium chloride is added to an aqueous solution of silver nitrate, a white precipitate is formed. Give the chemical equation of this reaction.
Answer:

Question 2.
Why does the reaction rate of a reaction increase in raising the temperature?
Answer:
On increasing temperature heat is supplied to the reactant. This energy breaks more bonds and thus speed up the chemical reaction. Foods kept at room temperature spoils faster than that kept in the refrigerator.

Question 3.
Define combination reaction. Give one example for an exothermic combination reaction.
Answer:
A combination reaction is a reaction in which two or more reactants combine to form a compound.
Eg: C_(s) + O_2(g) → CO_2(g) + heat

Question 4.
Differentiate reversible and irreversible reactions.
Answer:

VI. Answer in detail:

Question 1.
What are called thermolysis reactions?
Answer:
Thermal decomposition reactions are called ‘thermolysis’ reaction. In this type of reaction, the reactant is decomposed by applying heat. There are two types of thermolysis reactions. They are:
(i) Compound to element / element decomposition:
A compound is decomposed into two elements.
Eg:

(ii) Compound to compound / compound decomposition:
A compound is decomposed into two compounds.
Eg:

Question 2.
Explain the types of double displacement reactions with examples.
Answer:
There are two major classes of double displacement reactions. They are,
(i) Precipitation Reactions: When aqueous solutions of two compounds are mixed, if they react to form an insoluble compound and a soluble compound, then it is called precipitation reaction.
\(\mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2(\mathrm{aq})}+2 \mathrm{KI}_{(\mathrm{aq})} \rightarrow \mathrm{PbI}_{2(\mathrm{s})} \downarrow+2 \mathrm{KNO}_{3(\mathrm{aq})}\)

(ii) Neutralisation Reactions: Another type of displacement reaction in which the acid reacts with the base to form a salt and water. It is called ‘neutralisation reaction’ as both acid and base neutralize each other.
\(\mathrm{NaOH}_{(\mathrm{aq})}+\mathrm{HCl}_{(\mathrm{aq})} \rightarrow \mathrm{NaCl}_{(\mathrm{aq})}+\mathrm{H}_{2} \mathrm{O}_{(\mathrm{l})}\).

Question 3.
Explain the factors influencing the rate of a reaction.
Answer:
Important factors that affect rate of a reaction are:

1. Nature of the reactants
2. Concentration of the reactants
3. Temperature
4. Catalyst
5. Pressure
6. Surface area of the reactants

1. Nature of the reactants : The reaction of sodium with hydrochloric acid is faster than that with acetic acid, because Hydrochloric acid is a stronger acid than acetic acid and thus more reactive. So, the nature of the reactants influence the reaction rate.
2Na_(s) + 2HCl_(aq) → 2NaCl_(aq) + H_2(g) (fast)
2Na_(s) + 2CH₃COOH_(aq) → 2CH₃COONa_(aq) + H_2(g) (slow)

2. Concentration of the reactants : Changing the amount of the reactants also increases the reaction rate. More the concentration, more particles per volume exist in it and hence faster the reaction. Granulated zinc reacts faster with 2M hydrochloric acid than 1M hydrochloric acid.

3. Temperature : Most of the reactions go faster at higher temperature. Because adding heat to the reactants provides energy to break more bonds and thus speed up the reaction. Calcium carbonate reacts slowly with hydrochloric acid at room temperature. When the reaction mixture is heated the reaction rate increases.

4. Pressure : If the reactants are gases, increasing their pressure increases the reaction rate. This is because, on increasing the pressure the reacting particles come closer and collide frequently.

5. Catalyst : A catalyst is a substance which increases the reaction rate without being consumed in the reaction. In certain reactions, adding a substance as catalyst speeds up the reaction. For example, on heating potassium chlorate, it decomposes into potassium chloride and oxygen gas, but at a slower rate. If manganese dioxide is added, it increases the reaction rate.

6. Surface area of the reactants : Powdered calcium carbonate reacts more readily with hydrochloric acid than marble chips. Because, powdering of the reactants increases the surface area and more energy is available on collision of the reactant particles. Thus, the reaction rate is increased.

Question 4.
How does pH play an important role in everyday life?
Answer:

• The pH of blood is almost 7.4. Any increase or decrease in this value leads to diseases
• Citrus fruits require slightly alkaline soil, while rice requires acidic soil and sugarcane requires neutral soil.
• If the pH of rainwater becomes less than 7, it becomes acid rain which is harmful in day-to-day life.
• pH changes cause tooth decay.
• During indigestion, the stomach produces too much acid and this causes pain and irritation.

Question 5.
What is chemical equilibrium? What are its characteristics?
Answer:
Chemical equilibrium is a state of a reversible chemical reaction where the,
Rate of forward reaction = Rate of backward reaction.
No change in the amount of the reactants and products takes place.
Characteristics of equilibrium:

1. In a chemical equilibrium, the rates of the forward and backward reactions are equal.
2. The observable properties such as pressure, concentration, colour, density, viscosity etc., of the system remain unchanged with time.
3. The chemical equilibrium is a dynamic equilibrium, because both the forward and backward reactions continue to occur even though it appears static externally.
4. In physical equilibrium, the volume of all the phases remain constant.

VII. HOT Questions:

Question 1.
A solid compound ‘A’ decomposes on heating into ‘B’ and a gas ‘C’ On passing the gas ‘C’ through water, it becomes acidic. Identify A, B and C.
Answer:
A – CaCO₃, solid compound
‘A’ decomposes on heating into ‘B’ and a gas ‘C’.

On passing the gas CO₂ through water, it becomes acidic.

A – CaCO₃, Calcium carbonate
B – CaO, Calcium oxide
C – CO₂, Carbondioxide gas

Question 2.
Can a nickel spatula be used to stir copper sulphate solution? Justify your answer.
Answer:
No, nickel spatula cannot be used to stir the copper sulphate solution. Actually, on the basis of activity series, nickel is more reactive than copper, so nickel will displace copper from its solution and copper will be deposited on nickel spatula.

VIII. Solve the following problems:

Question 1.
Lemon juice has a pH 2, what is the concentration of H⁺ ions?
Answer:
pH = – log [H⁺]
[H⁺] = antilog of [-pH]
= antilog [-2]
[H⁺] = 10^-2 M
[OR]
PH = – log [H⁺]
[H⁺] = 10^-pH
[H⁺] = 10^-2M

Question 2.
Calculate the pH of 1.0 × 10^-4 molar solution of HNO₃.
Answer:
pH = – log [H⁺]
HNO3 → H⁺ + NO₃^–
pH = -log [1 × 10^-4]
= -(-4)log₁₀ 10 = 4
pH = 4

Question 3.
What is the pH of 1.0 x 10^-5 molar solution of KOH?
Answer:
KOH → K⁺ + OH^–
pOH = -log[OH^–]
= -log [1 × 10^-5]
pOH = 5
pH + pOH = 14
∴ pH of KOH = 14 – 5 = 9
pH = 9

Question 4.
Laundry detergent has a pH 8.5, What is the concentration of H⁺ ions?
Answer:
pH = 8.5
pH = – log [H⁺]
[H⁺] = 10^-pH
[H⁺] = 10^-8.5
[H⁺] = 3.16 × 10^-9 M

Question 5.
The hydroxide ion concentration of a solution is 1 × 10^-11M. What is the pH of the solution?
Answer:
[OH^–] = 1 × 10^-11 M
pOH = – log[OH^–]
= – log[1 × 10^-11]
= -log₁₀1 – log₁₀10^-11
= -(-11) log₁₀10 = 11
pOH = 11
pH + pOH = 14
pH = 14 – 11
pH = 3

Samacheer Kalvi 10th Science Types of Chemical Reactions Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The unit of rate of a reaction is:
(a) dm³/mol
(b) dm^-3
(c) mol dm^-3
(d) mol
Answer:
(c) mol dm^-3

Question 2.
As the molecule is dissociated by the absorption of heat it is otherwise called as ______.
(a) Thermolysis
(b) Photolysis
(c) Electrolysis
(d) None of these.
Answer:
(a) Thermolysis

Question 3.
The chemical formula of marble is:
(a) CaCO₃
(b) MgCO₃
(c) Na₂CO₃
(d) PbCO₃
Answer:
(a) CaCO₃

Question 4.
As the decomposition is caused by light, this kind of reaction is called ______.
(a) Thermolysis
(b) Photolysis
(c) Electrolysis
(d) None of these.
Answer:
(b) Photolysis

Question 5.
Fluorine will displace the following halide ion from the solution:
(a) chloride
(b) bromide
(c) iodide
(d) all the above
Answer:
(d) all the above

Question 6.
The decomposition of AgBr into grey coloured silver metal is an example of ……… reaction.
(a) compound to element/element
(b) compound to compound/compound
(c) combination
(d) neutralization
Answer:
(a) compound to element/element

Question 7.
The Metathesis reaction among the following is:
(a) C₃H_8(g) +5O_2(g) → 3CO_2(g) + 4H₂O + heat
(b) Zn_(s) + CuSO_4(aq) → ZnSO_4(aq) + Cu_(s)
(c) HNO_3(aq) + NH₄OH_(aq) → NH₄NO_3(aq) + H₂O_(l)

Answer:
(c) HNO_3(aq) + NH₄OH_(aq) → NH₄NO_3(aq) + H₂O_(l)

Question 8.
KI and Pb(NO₃)₂ solutions are mixed to give a precipitate. What is the colour of the precipitate?
(a) White
(b) Brown
(c) Red
(d) Yellow.
Answer:
(d) Yellow

Question 9.
The pH of rain water is approximately:
(a) 7
(b) 8
(c) 4
(d) 14
Answer:
(a) 7

Question 10.
Most of the reactions go faster at ______.
(a) low temperature
(b) moderate temperature
(c) 0°C
(d) high temperature.
Answer:
(d) high temperature

II. Fill in the blanks.

1. A chemical equation provides information on the ……….. of the substances and the reaction condition.
2. The symbol ‘aq’ in a chemical equation represent the physical state of the substance as ……….
3. 2Na_(s) + Cl_2(g) → 2NaCl_(s) represent the combination reaction between a ……… and ……
4. After white washing with a solution of slaked lime a thin layer of ……….. is formed.
5. Reactions in which heat is absorbed is called ……….. reactions.
6. Electrolytic refining of copper is based on ……….. reaction.
7. When 10^-6 mole of a monobasic strong acid is dissolved in water, the pH of the solution is ………..
8. When pH of a solution is 2, the [H⁺] in mol/L is ……….
9. Combustion of coal is an example of ………. reaction.
10. [ ] represents the concentration of either the reactant or product in ……….
Answer:
1. physical state
2. aqueous solution
3. metal, non-metal
4. CaCO₃
5. endothermic
6. electrolytic decomposition
7. 6
8. 1 × 10^-2
9. irreversible
10. mol/Lit

III. Match the following.

Question 1.
Match the following table:

Answer:
A. (v)
B. (iii)
C. (iv)
D. (ii)
E. (i)

Question 2.
Match the following table:

Answer:
A. (v)
B. (iv)
C. (i)
D. (iii)
E. (ii)

Question 3.
Match the following table:

Answer:
A. (iii)
B. (v)
C. (iv)
D. (ii)
E. (i)

Question 4.
Match the following table:

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

IV. True or False: (if false give the correct statement)

1. Formation of calcium silicate from silica and calcium oxide is a combination reaction.
2. Most of the combination reactions are endothermic in nature.
3. Decomposition of mercuric oxide into mercury and O₂ is an example of . photolysis.
4. Chlorine can displace fluoride ion from its aqueous solution.
5. Magnesium is more reactive than iron.

Answer:

1. True
2. False – Most of the combination reactions are exothermic in nature.
3. False – Decomposition of mercuric oxide into mercury and O₂ is an example of thermolysis.
4. False – Chlorine is less reactive than Fluorine, so it cannot displace fluoride ion from its aqueous solution.
5. True

V. Short answer questions:

Question 1.
Write a note on double displacement reaction with an example.
Answer:
When two compounds react, if their ions are interchanged, then the reaction is called double displacement reaction.
Eg: NaOH_(aq) + HCl_(aq) → NaCl_(aq) + H₂O

Question 2.
Identify the wrong statements and correct them.

1. Sodium benzoate is used in food preservative.
2. Nitric acid is not used as fertilizer in agriculture.
3. Sulphuric acid is called the king of chemicals.
4. The pH of acid is greater than 7.
5. Acetic acid is used in aerated drinks.

Answer:

1. Correct statement.
2. Wrong statement. Nitric acid is used as a fertilizer in agriculture.
3. Correct statement.
4. Wrong statement. The pH of the acid is lesser than 7.
5. Wrong statement. Carbonic acid is used in aerated drinks.

Question 3.
Why a combustion reaction may be called as an exothermic oxidation?
Answer:
In a combustion reaction heat is evolved, it is an exothermic reaction. As oxygen is added, it is also an oxidation. So, combustion may be called as an exothermic oxidation.

Question 4.
Take two conical flasks. Label them as I and II. Take a small amount of copper sulphate solution in the first conical flask. Take a small amount of granulated zinc in the second conical flask. Allow the copper sulphate solution to react with the zinc.

1. Name the type of reaction.
2. Say whether the metal zinc is more reactive or less reactive.
3. Write a complete and balanced reaction.
4. Say whether this change is reversible or irreversible.

Answer:

1. The reaction taken place is displacement reaction.
2. Metal zinc is more reactive.
3. Balanced chemical equation.
   \(\mathrm{Zn}_{(\mathrm{s})}+\mathrm{CuSO}_{4(\mathrm{aq})} \rightarrow \mathrm{ZnSO}_{4(\mathrm{aq})}+\mathrm{Cu}_{(\mathrm{s})} \downarrow\)
4. This change is an irreversible change.

Question 5.
What is an irreversible reaction? Give an example.
Answer:
The reaction that cannot be reversed is called irreversible reaction. The irreversible reactions are unidirectional, i.e., they take place only in the forward direction. Consider the combustion of coal into carbon dioxide and water.

Question 6.
Define the rate of a reaction.
Answer:
“Rate of a reaction is the change in the amount or concentration of any one of the reactants or products per unit time”.
Consider the following reaction,
A → B
The rate of this reaction is given by
Rate = –\(\frac{d[A]}{dt}\) = +\(\frac{d[B]}{dt}\)
Where,
[A] – Concentration of A
[B] – Concentration of B
The negative sign indicates the decrease in the concentration of A with time. The positive sign indicates the increase in the concentration of B with time.

Question 7.
What is meant by combination reaction? Give an example.
Answer:
A reaction in which a single product is formed from two or more reactants is known combination reaction.
2Mg + O₂ → 2MgO.

Question 8.
What is a catalyst?
Answer:
A catalyst is a substance which increases the reaction rate without being consumed in the reaction.

Question 9.
Define Displacement reaction. Give an example.
Answer:
The reaction in which a more reactive element displaces a less reactive element from its compound is called displacement reaction.
\(\mathrm{Pb}+\mathrm{CuCl}_{2} \longrightarrow \mathrm{PbCl}_{2}+\mathrm{Cu} \downarrow\)
Lead displaces copper from copper chloride solution.

Question 10.
When a aerated soft drink bottle is kept open it will go flat. Why?
Answer:
(i) In the sealed aerated soft drink bottle, the dissolved CO₂, in the form of carbonic acid and gaseous CO₂ are in equilibrium.
(ii) When we open the bottle the gaseous CO₂ will escape and the dissolved CO₂ begins to undissolve to the gas phase to maintain the equilibrium. So when we keep the bottle open for a long time it will go flat with all the dissolved CO₂ gone.

Question 11.
Can copper displace zinc or lead from their salt solutions?
Answer:
No, copper cannot displace zinc or lead from their salt solutions. Because copper is less reactive than zinc and lead.

Question 12.
What is called as acid rain?
Answer:
The pH of rain water is approximately ‘7’ but when the air is polluted with oxides of S and N, they get dissolved in the rain water and make its pH less than 7, then it is called acid rain.

Question 13.
Write the differences between combination and decomposition reaction.
Answer:

VI. Answer in detail:

Question 1.
Two acids ‘A’ and ‘B’ were kept in beakers. Acid ‘A’ undergoes partial dissociation in water, whereas acid ‘B’ undergoes complete dissociation in water.

1. Of the two acids ‘A’ and ‘B’ which is weak acid and which is strong acid?
2. What is a weak acid?
3. What is a strong acid?
4. Give one example of each.

Answer:

1. Of the two acids ‘A’ and ‘B’, ‘A’ is a weak acid and ‘B’ is a strong acid.
2. A weak acid is the one which ionises partially when dissolved in water.
3. A strong acid is the one which ionises completely when dissolved in water.
4. Weak acid – Acetic acid(CH₃COOH)
   Strong acid – Sulphuric acid (H₂SO₄).

Question 2.
Sodium hydroxide and HCl acid react as shown in this equation
NaOH_(aq)4 + HCl_(aq) → NaCl_(aq) + H₂O
(i) Which type of chemical reaction is this?
Answer:
Neutralization reaction

(ii) The reaction is exothermic. Explain what that means?
Answer:
When heat is evolved during a chemical reaction it is called exothermic.

(iii) Differentiate exothermic and endothermic reaction.
Answer:
Exothermic :

1. Heat is evolved.
2. Temperature increases.

Endothermic :

1. Heat is absorbed.
2. Temperature decreases.

(iv) What happens to the temperature of the solution as the chemicals react?
Answer:
Temperature of the solution increases.

Question 3.
Take two conical flasks. Label them as I and II. Take a small amount of CuSO₄ in the I conical flask and small amount of granulated Zinc in the II conical flask. Allow the CuSO₄ solution to react with Zinc.
(i) Name the type of reaction.
Answer:
Displacement reaction.

(ii) Say whether the metal Zn is more reactive or less reactive.
Answer:
Zinc is more reactive than Copper.

(iii) Write the complete and balanced reaction.
Answer:
Zn_(s)+ CuSO_4(aq) → ZnSO_4(aq) + Cu_(s)↓

(iv) Say whether this change is reversible or irreversible
Answer:
Irreversible.

Question 4.
Suggest a reason for each observation given below.

1. In fireworks, powdered magnesium is used rather than magnesium ribbon.
2. Zinc and dilute H₂SO₄ react much more quickly when a few drops of copper sulphate solutions are added.
3. The reaction between magnesium carbonate and dilute hydrochloric acid speeds up when some concentrated HCl is added.

Answer:

1. In fireworks, powdered magnesium is used because it has more surface area than magnesium ribbon. Because of more surface area, powdered magnesium reacts faster than magnesium ribbon.
2. Zinc and dilute H2SO4 react much more quickly when a few drops of copper sulphate solution is added. Copper sulphate acts as a catalyst which increases the rate of the reaction.
3. When the concentration of the reactants increases, the rate of the reaction also increases. So the reaction between magnesium carbonate and dilute hydrochloric acid speeds up by the addition of some concentrated HCl.

VII. Hot Questions:

Question 1.

Answer:
According to the rate Law for the reaction.
2N₂O₅ → 4NO₂ + O₂

2K₁ = K₂ = 4K₃ [neglecting negative and positive signs]

Question 2.
When solutions of silver nitrate and potassium bromide are mixed, a pale yellow precipitate is formed.
The ionic equation for the reaction is Ag⁺ + Br^– → AgBr

1. (a) What is the name of the pale yellow precipitate?
   (b) Is it soluble or insoluble?
2. Is the formation of silver bromide precipitate, a result of redox reaction or not? Justify your answer.
3. What is this type of reaction called?

Answer:

1. (a) The pale yellow precipitate is silver bromide.
   (b) Silver bromide is sparingly soluble.
2. Yes, the formation of silver bromide precipitate is due to redox reaction. Ag⁺ gains electron (reduction) and Br^– loses electron (oxidation). So it is a redox reaction.
3. This reaction is a double displacement reaction.

VIII. Numericals:

Question 1.
The hydrogen ion concentration of a fruit juice is 3.3 × 10^-2M. What is the pH of the juice? Is it acidic or basic?
Answer:
[H⁺] = 3.3 × 10^-2 M
Formula:
pH = -log[H⁺]
pH = -log[3.3 × 10^-2]
= -[log 3.3 + log 10^-2]
= -[0.5185 – 2 log₁₀10]
= -0.5185 + 2 log₁₀10 [log₁₀10 = 1]
= -0.5185 + 2
pH = 1.4815
Since pH is less than 7, the solution is acidic.

Question 2.
If a solution has a pH of 7.41, determine its H⁺ concentration.
Answer:
pH = 7.41
Formula:
[H⁺] = antilog[-pH]
= antilog[-7.41] = 10^-7.41
= 3.89 × 10^-8M

Question 3.
The pH of a solution is 5.5 at 25°C. Calculate its [OH^–].
Answer:
pH = 5.5
Since pH + pOH = 14
pOH = 14 – pH
= 14 – 5.5 = 8.5
[OH^–] = 10^-pOH
= 10^-8.5
= 3.16 × 10^-9M
(OR)
[OH^–] = antilog[-8.5]
= 3.16 × 10^-9M
[OH^–] = 3.16 × 10^-9M

Question 4.
Calculate the pH of 0.001 M HCl solution.
Answer:
Since HCl is a strong acid, it dissociates
HCl → H⁺ + Cl^–
[H⁺] = [HCl] = 0.001 M
[H⁺] = 1 × 10^-3M
pH = -log[H⁺]
= -log[1 × 10^-3]
pH = 3

Question 5.
The hydrogen ion concentration of a solution is 1 × 10^-8M.
(i) What is the pH of the solution?
Answer:
pH = -log[1 × 10^-8]
pH = 8

(ii) What is the pOH of the solution?
Answer:
pOH = 14 – 8
= 6

(iii) Is the given solution acidic or basic?
Answer:
Acidic

Question 6.
Calculate the pH of 0.02 M Ba(OH)₂, Ba(OH)₂ solution is a strong electrolyte.
Answer:
[Ba(OH)₂] = 0.02 M
Ba(OH)₂ → Ba²⁺ + 2OH^–
[OH^–] = 2[Ba(OH)₂]
= 2 × 0.02 = 0.04 M
pOH = – log[0.04]
= -log[4 × 10^-2]
= -[log 4 + log 10^-2]
= -[0.6020 – 2 log 10]
pOH = -0.6020 + 2 × 1
= 1.398
pH = 14 – 1.398
= 12.602

Students can download 10th Social Science Geography Chapter 3 Components of Agriculture Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 3 Components of Agriculture

Samacheer Kalvi 10th Social Science Components of Agriculture Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
The soil which is rich in iron oxides is
(a) Alluvial
(b) Black
(c) Red
(d) Alkaline
Answer:
(c) Red

Question 2.
Which of the following organization has divided the Indian soils into 8 major groups?
(a) Indian Council of Agricultural Research
(b) Indian Meteorological Department
(c) Soil Survey of India
(d) Indian Institute of Soil Science
Answer:
(a) Indian Council of Agricultural Research

Question 3.
The soils formed by the rivers are:
(a) Red soils
(b) Black soils
(c) Desert soils
(d) Alluvial soils india.
Answer:
(d) Alluvial soils india.

Question 4.
……….. dam is the highest gravity in India.
(a) Hirakud dam
(b) Bhakra Nangal dam
(c) Mettur dam
(d) Nagaijuna Sagar dam
Answer:
(b) Bhakra Nangal dam

Question 5.
……………… is a cash crop.
(a) Cotton
(b) Wheat
(c) Rice
(d) Maize
Answer:
(a) Cotton

Question 6.
Black soils are also called as ………..
(a) Arid soils
(b) Saline soils
(c) Regur soils
(d) Mountain soils
Answer:
(c) Regur soils

Question 7.
The longest dam in the world is:
(a) Mettur dam
(b) Kosi dam
(c) Hirakud dam
(d) Bhakra Nangal dam
Answer:
(c) Hirakud dam

Question 8.
The leading producer of rice in India is ……….
(a) Punjab
(b) Maharashtra
(c) Uttar Pradesh
(d) West Bengal
Answer:
(c) Uttar Pradesh

Question 9.
Which crop is called as “Golden Fibre” in India?
(a) Cotton
(b) Wheat
(c) Jute
(d) Tobacco
Answer:
(c) Jute

Question 10.
The state which leads in the production of coffee is ……….
(a) West Bengal
(b) Karnataka
(c) Odisha
(d) Punjab
Answer:
(b) Karnataka

II. Consider the given statements and choose the right option given below

Question 1.
Assertion (A): Horticulture involves the cultivation of fruits, vegetables, and flowers.
Reason (R): India ranks first in the world in the production of mango, banana, and citrus fruits.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 2.
Assertion(A): Alluvial soil is formed by the deposition of eroded and decayed materials brought by the rivers.
Reason(R): Paddy and wheat are grown well in the soil.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true and (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(b) Both (A) and (R)are true and (R) does not explain (A)

III. Pick the odd one out

Question 1.
(a) Wheat
(b) Rice
(c) Millets
(d) Coffee
Answer:
(d) Coffee

Question 2.
(a) Khadar
(b) Bhangar
(c) Alluvial soil
(d) Black soil
Answer:
(d) Black soil

Question 3.
(a) Inundation canals
(b) Perennial canals
(c) Tanks
(d) Canals
Answer:
(c) Tanks

IV. Match the following

Answer:
A. (iv)
B. (iii)
C. (v)
D. (i)
E. (ii)

V. Answer in brief

Question 1.
Define soil.
Answer:
Soil is the uppermost layer of the land surface, usually composed of minerals, organic matter, living organisms, air and water. Its formation is mainly related to the parent rock material, surface relief, climate and natural vegetation.

Question 2.
Name the types of soil found in India.
Answer:
There are 8 major groups of soil found in India classified by the Indian Council of Agricultural Research. They are

1. Alluvial soil
2. Black soil
3. Red soil
4. Forest and Mountain soil
5. Arid and Desert soil
6. Laterite soil
7. Saline and Alkaline soil
8. Peaty and Marshy soil

Question 3.
State any two characteristics of black cotton soil.
Answer:

1. This soil is rich in calcium carbonate, magnesium, potash, lime and iron but deficient in phosphorous. It is clayey and impermeable which has great capacity to retain moisture for a long time.
2. It becomes sticky when wet but develops cracks during dry summer season. The soil is suited for dry farming due to its high moisture retentivity.

Question 4.
What is Multipurpose project?
Answer:

1. Multipurpose projects are the River valley projects.
2. Dams are constructed across rivers aims to serve many purposes such as irrigation, power generation, water supply, controlling floods, navigation, development of fisheries etc.

Question 5.
Define Agriculture.
Answer:
Agriculture is the process of producing food for people, fodder for cattle, fiber and many other desired products by the cultivation of certain plants and the raising of domesticated animals

Question 6.
State the types of agriculture practices in India?
Answer:

1. Owing to physical environment and culture the following cultivation systems prevail in India.
2. Subsistence farming
3. Intensive farming
4. Dry farming
5. Mixed farming agriculture
6. Terrace cultivation

Question 7.
Name the seasons of agriculture in India.
Answer:

1. Kharif Season
2. Rabi Season
3. Zaid Season

Question 8.
Mention the plantation crops of India.
Answer:

1. Plantation crops are mainly cultivated for the purpose of exports.
2. These crops are cultivated in large estates on hilly slopes.
3. Tea, coffee, rubber and spices are the main plantation crops of India.

Question 9.
What do you mean by livestock?
Answer:
Livestocks is defined as farm animals who are raised to generate a profile. It is an integral component of the farming system in India.

Question 10.
Write a brief note on the categories of fisheries in India?
Answer:
In India fisheries are categorised into two.They are marine or sea fisheries and inland or fresh water fisheries.

Marine or Sea fisheries:

1. It includes coastal off-shore and deep sea fishing mainly on continental shelf upto a depth of 200 mts.
2. Kerala leads in Marine fish production.

Inland or Fresh water fisheries:

1. Rivers, lakes, canals, reservoirs, ponds tanks etc are the sources of fresh water fisheries,
2. Andhra Pradesh is leading in the fresh water fisheries.
3. About 50% of the country’s total fish production comes from inland fisheries.

VI. Give reasons

Question 1.
Agriculture is the backbone of India.
Answer:
Agriculture provide food for the entire population. It supplies raw materials to the agro-based industries. It contributes to export trade. So, agriculture is the backbone of India.

Question 2.
Rain water harvesting is necessary.
Answer:
India experiences Tropical monsoon climate. Rainfall in India is seasonal, irregular and uneven and highly eractic. Hence it is necessary’ to save rain water when it is available and use in times of need. In order to prevent surface . run off Rainwater harvesting is needed.

Question 3.
Small farms are predominant in India.
Answer:
The predominant type of Indian agriculture is subsistence farming. In this agriculture land holding is small and half of the production is used for family consumption and the rest is sold in the nearby markets. The farmers concentrate on stage food crops like rice and wheat. As the farmers are poor, they can’t apply the modem inputs which cost more.

VII. Distinguish between the following

Question 1.
Rabi and Kharif crop seasons.
Answer:
Rabi crop season:

1. Rabi crop season is from October – March.
2. Seeds are sown in winter and harvested before summer.
3. Major crops of this season are mainly Wheat, Mustard, Maize etc.

Kharif crop season:

1. Kharif crop season is from June – September.
2. Seeds are sown after the summer monsoon and harvested before winter.
3. Major crops are Rice, Cotton, Groundnut, Turmeric etc.

Question 2.
Inundation canal and perennial canal.
Answer:
Inundation canal:

1. Undependable source of irrigation.
2. Operational only during flood in rivers and not have weir system to regulate water.

Perennial canal:

1. Dependable source of irrigation.
2. Have weir system through barrage to regulate water from perennial rivers or dams.

Question 3.
Marine fishing and Inland fishing.
Answer:
Marine fishing:

1. Marine fishing includes coastal, off¬shore and deep sea fishing mainly on the continental shelf upto a depth of 200m.
2. Kerala is the leading producer in marine fishing.

Inland fishing:

1. Inland fishing is done in rivers, lakes, canals, ponds, tanks, reservoirs etc.
2. Andhra Pradesh, West Bengal, Gujarat, Kerala and TamilNadu are the leading states.

Question 4.
Alluvial soils and Black soils.
Answer:
Alluvial soil:

1. Formed by the sediments deposited by the rivers and streams.
2. Silt clay, sandy and loamy in nature.
3. Found in the river valleys and plains.
4. Rice, wheat, sugarcane grow well in this soil.

Black soil:

1. Formed by the disintegration of basalt rocks.
2. Sticky when wet develops cracks when dry.
3. Found in plateau region especially in Deccan trap.
4. Cotton, sugarcane and tobacco grow well in this soil.

VIII. Answer in a paragraph

Question 1.
State the types of soil in India and explain the characteristics and distribution of soil.
Answer:

Question 2.
Write about any two multipurpose projects of India.
Answer:
A comprehensive river valley project which serves a number of purposes simultaneously is called a “Multi purposes project”.

1. The Bhakra Nangal Project: India’s biggest multipurpose river valley project is ‘Bhakra Nangal Project’. It has been built at a strategic point where two hills on either side of the Sutlej are very close to each other. It is the highest gravity dam in the world. Its length is 226 metres from the river bed. The canals taken out are 1100 kilometres long. The ‘Nangal Power Plant’ on the Sutlej produces electricity, and serves the states of Himachal Pradesh, Punjab, Haryana, Rajasthan and New Delhi. The distributaries are 8400 km in length. It irrigates an area of 1.4 million hectares.

2. Indira Gandhi Project: This project is an ambitious scheme to bring new areas under irrigation so that more areas could be cultivated. The waters of the River Beas and the Ravi are diverted to the River Sutlej. The ‘Pong’ Dam on the River Beas has been constructed to divert the Beas water into the Sutlej in a regulated manner. So that ‘Rajasthan canal’, the longest irrigation canal in the world can irrigate Gandhi Nagar, Bikaner and Jaisalmer districts of North West Rajasthan, (i.e) a part of Thar desert. The main canal now called ‘Indira Gandhi Canal’ is 468 km long runs entirely in Rajasthan, Western of Sutlej, Beas and Ravi are now being fully utilised for irrigating thirsty lands of South Western parts of our country.

Question 3.
Bring out the characteristics of intensive and Plantation farming.
Answer:
Characteristics of Intensive farming:

1. Farming is done with intensification and mechanisation system to maximize yields from available land.
2. In this farming heavy use of pesticides and chemical fertilizers have been applied.
3. It has also been applied to the raising of live stock being held indoor as factory farms.
4. Plantation fanning.
5. Single crop raised on a large area testates).
6. Crops are grown mainly for export purpose,
7. The plantations are mostly owned by companies.

Question 4.
Examine the geographical conditions favourable for the cultivation of rice and wheat.
Answer:
Rice:
Rice is an indigenous crop. India is the second-largest producer of rice in the world. It is a tropical crop which is grown well in alluvial plains and river deltas. It requires a mean monthly temperature of 24°C and an average rainfall of 150 cm and deep fertile alluvial soil for its growth. It also needs an abundant supply of cheap labour. In areas of less rainfall particularly in Punjab and Haryana, it is grown with the help of irrigation.
Rice in India is sown in three ways:

1. Broadcasting,
2. Ploughing or drilling, and
3. Transplanting.

Due to increased use of High Yielding Variety (HYV) seeds (CR Dhan 205, AR Dhan 306, CRR 451 etc.), many of the indigenous varieties were disappeared. In 2016, the first 10 leading rice-producing states are West Bengal (First in India) Uttar Pradesh, Punjab, Tamil Nadu, Andhra Pradesh, Bihar, Chhattisgarh, Odisha, Assam, and Haryana.

Wheat:
Wheat is a temperate crop. Its cultivation is mainly confined to the northwestern part of India. India produces both winter wheat and spring wheat. It is the second most important food crop of the country, after rice.

It requires 10-15°C at the time of sowing and 20-25°C at the time of ripening of grains. Over 85% of India’s wheat production comes from 5 states namely Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh. Apart from these regions, the black soil tract of the Deccan covering parts of Maharashtra and Gujarat also contribute a major wheat production.

IX. HOTS Questions

Question 1.
Can you imagine a world without agriculture?
Answer:
Agriculture is the art and science of cultivating the soil, growing crops and raising livestock. It includes the preparation of plant and animal products for people to use and their distribution to markets.

Agriculture provides most of the world’s food and fabrics. Cotton, wool and leather are all agricultural products. It also provides wood for construction and paper products.

A world without agriculture would be very different compared to the world we live in today. It is easy for us as humans to take for granted things when we don’t really know how they are grown or produced. Without agriculture, we may not get food and clothing. Without timber, we may not be able to build houses and furniture. We may also be deprived of some everyday-products like soap, paper and ethanol, which are made up of some sort of agricultural by-product. Modern medicine also depends on agriculture. Without agriculture, we wouldn’t be here. We must always be thankful for this industry and for those involved in the various activities related to it.

Question 2.
Can you give solutions for the prevailing water disputes in South India (construction of dams / raising of dams / cleaning of tanks}?
Answer:

1. Construction of check dams: In order to prevent surface run off water • during heavy rains. Check dams has to be constructed to regulate the flow of water.
2. Raising of dams: Improves the storage capacity, Strengthening the dams is a must.
3. Cleaning of tanks: Preventing encroachment by strict legal action, desilting the tanks and deepening it in the local areas will provide water supply to the locality, as well as to maintain the areas of ground water level cleaning of tanks is a must

X. Map exercise

Question 1.
Demarcate the major tracts of alluvial soils.
Answer:

Question 2.
Delineate the main regions of black soil.
Answer:

Question 3.
Locate the Hirakud dam, Mettur dam and Damodar dam.
Answer:

Question 4.
Shade the regions of jute cultivation.
Answer:

Question 5.
Mark any three tea and coffee growing areas.
Answer:

Question 6.
Demarcate the regions of desert soil.
Answer:

Question 7.
Locate the fishing hubs: Tuticorin, Chennai,Cochin, Mumbai, Machiiipatnam
Answer:

Question 8.
Demarcate: Cauvery delta, Godavari delta.
Answer:

TB. PNo: 115
Activity 1:

Question 1.
Soil Texture (sand, silt, clay) influence on some properties of soils including water holding capacity. Find out water holding capacity of soils which given above based on following table.
Answer:

TB. PNo: 131
Activity 2:

Question 1.
Complete the following table by your day to day life experience.

Answer:

Samacheer Kalvi 10th Social Science Components of Agriculture Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
……………… soil is formed by the process of leaching.
(a) Alluvial
(b) Black
(c) Laterite
(d) Arid
Answer:
(c) Laterite

Question 2.
Cotton is a ………
(a) food crop
(b) cash crop
(c) dry crop
Answer:
(b) cash crop

Question 3.
……………… is one of the method of soil conservation.
(a) Deforestation
(b) Irrigation
(c) Water logging
(d) Afforestation
Answer:
(d) Afforestation

Question 4.
The “rice bowl of Tamil nadu” is ………..
(a) Madurai
(b) Chennai
(c) Thanjavur
Answer:
(c) Thanjavur

Question 5
……………… are useful for the diversion of flood water from the rivers during rainy season.
(a) Perennial canals
(b) Inundation canals
(c) Open wells
(d) Tube wells
Answer:
(b) Inundation canals

Question 6
The type of fanning which is practised in Punjab and Haryana is ………
(a) subsistence farming
(b) commercial farming
(c) wet farming
Answer:
(b) commercial farming

Question 7.
……………… project is constructed on the river Kaveri in TamilNadu.
(a) Tehri Dam
(b) Kosi Dam
(c) Mettur Dam
(d) Horakud Dam
Answer:
(c) Mettur Dam

Question 8.
In the regions with abundant rainfall ……. is grown.
(a) millet
(b) wheat
(c) rice
Answer:
(c) rice

Question 9.
The traditional farming method that results in low productivity is:
(a) mixed farming
(b) shifting agriculture
(c) intensive farming
(d) subsistence farming
Answer:
(d) subsistence farming

Question 10.
One of the important zaid crops is ………….
(a) rice
(b) wheat
(c) watermelon
Answer:
(c) watermelon

Question 11.
First Live-stock census was conducted in India in the year:
(a) 1819
(b) 1919
(c) 1618
(d) 1981
Answer:
(b) 1919

Question 12.
The National Research Center on Plant Biotechnology was established in ………
(a) 1985
(b) 1980
(c) 1990
Answer:
(a) 1985

II. Consider the given statements and choose the right option given below

Question 1.
Assertion (A): Indian agriculture is largely dominated by food crops. Reason (R): India has a large population.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 2.
Assertion (A): Forest and mountain soils differ from region to region. Reason (R): Due to the absence of vegetative cover.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false
Hint: Reason is due to mechanical weathering caused by snow, rain, temperature variation depending on climate.

Question 3.
Assertion (A): Terrace farming method is practiced on hill and mountain slopes. Reason (R): The availability of land is limited and it checks soil erosion.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R)are true: (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(a) Both (A) and (R) are true and (R) explains (A)

Question 4.
Assertion (A): Pulses are usually rotated with other crops.
Reason (R): They are used as human food and feeding cattle.
(a) Both (A) and (R) are true and (R) explains (A)
(b) Both (A) and (R) are true and (R) does not explain (A)
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false
Hint: They are mostly leguminous in nature and fixes atmospheric nitrogen helps soil to regain its fertility.

III. Pick the odd one out

1. (a) Tea, (b) Sugarcane, (c) Cotton, (d) Ragi
2. (a) Khandsari, (b) Herrings, (c) Mackerels, (d) Eels
3. (a) Damodhar, (b) Mahanadi, (c) Kaveri, (d) Raingun
4. (a) Water wheel, (b) Sprinkler, (c) Open well, (d) poly house
5. (a) Blue Revolution, (b) soil erosion, (c) Green Revolution, (d) Soil erosion
6. (a) Fishing, (b) Kharif, (c) Rabi, (d) Zaid

Answer:

1. (d) Ragi
2. (a) Khandsari
3. (d) Raingun
4. (c) Open well
5. (d) Soil erosion
6. (a) Fishing

IV. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

Question 2.
Match the Column I with Column II.

Answer:
A. (ii)
B. (iv)
C. (v)
D. (i)
E. (iii)

Question 3.
Match the Column I with Column II.

Answer:
A. (vi)
B. (iii)
C. (ii)
D. (i)
E. (iv)
F. (v)

V. Answer in brief

Question 1.
Why is tank irrigation more prevalent in South India than North India?
Answer:
The undulated topography of peninsular region forms large depressions to collect water which become tanks. So the tank irrigation is more prevalent in South India than North India.

Question 2.
How laterite soils are formed?
Answer:
Laterite soils are formed in the regions where alternate wet and dry conditions prevail.
It is formed by the process of leaching.

Question 3.
Which is an acute problem in India? How?
Answer:
Soil degradation is an acute problem in India. According to a 2015 report of the Indian institute of remote sensing (IIRS). The estimated the amount of soil .erosion that occurred in India was 147 million hectares.
The main problems of the Indian soils are

1. Soil erosion
2. Degradation of Soil
3. Water-logging
4. Saline and Alkaline and
5. Salt Flats.

Question 4.
Draw a flow chart showing the sources of irrigation and their classification.
Answer:

Question 5.
Write few lines about Rain Gun.
Answer:
It is used to spread water like rain and used to serve for crops which used to grow up to 4 feet or high also but we have to adjust sprinklers height as per crop size, typical usage of Rain guns are in sugarcane, maize crops.

Question 6.
Name the food crops grown in India.
Answer:
Food crops that are grown in India include cereals and pulses amongst which rice, wheat, jowar, bajra, maize, barely, ragi, gram and tur are important.

Question 7.
Give short notes about Terrace cultivation.
Answer:
This is practised especially in hilly areas, where lands are of sloping nature. The hill and mountains slopes are cut to form terraces and the land is used in the same way as in permanent agriculture.

Question 8.
Name the five leading states that contribute 85% of India’s wheat production.
Answer:
Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh are the leading states in wheat production in India.

Question 9.
What are the products of Sugarcane?
Answer:
Sugarcane provides raw material for the sugar industry. Besides providing sugar, gur and Khandsari it supplies molasses for alcohol industry and bagasse for paper industry.

Question 10.
How jute is useful for trade?
Answer:

1. Jute fibre provides raw material for Jute industry.
2. It is used for manufactruing of gunny bags, carpets, hessian, ropes and strings, rugs, clothes, tarpaulins, upholstery etc.

Question 11.
What is the other name of ‘Shifting Agriculture1? Who practice shifting agriculture? and how it is called in different regions?
Answer:
‘Shifting Agriculture’ is also called as ‘Slash and bum’ Agriculture. The tribal people follow this type of agriculture. It is called by different names in different regions in India as follows.

Name	Place
Jhum	Assam
Poonam	Kerala
Podu	Andhra Pradesh, Odisha
Beewar, Mashan, Penda, Beera	Various parts of Madhya Pradesh

Question 12.
What is dry farming?
Answer:
Dry farming is the type of farming practiced in arid areas where there is lack of irrigation facilities. Crops grown in these areas can withstand dry conditions.

Question 13.
What are called cash crops? Give examples.
Answer:
Crops which are cultivated for commercial purpose are called cash crops, eg: Sugarcane, tobacco, fibre crops and oil seeds.

Question 14.
Which is the largest oil seeds producing state? What is the position of India in oil seeds production in the world?
Answer:
Gujarat is India’s largest oil seeds producing state. India is the second largest producer of oil seeds in the world next to China.

Question 15.
Define Green Revolution.
Answer:
The process of improving and increasing the production of food crops using modem techniques is referred as Green Revolution.

Question 16.
Mention the different breeds of cattle population in India.
Answer:
Cattle population in India belongs to different breeds. They are

1. Milch breed
2. Draught breed
3. Mixed or General breed

VI. Give Reasons

Question 1.
Tank irrigation is popular in peninsular India.
Answer:
The undulating relief, absence of perennial rivers, Impermeable rock structure and natural depression are the reasons for having tank irrigation most popular in Peninsular India.

Question 2.
Why tea is grown on the hill slopes?
Answer:
Tea plants require high rainfall but its roots cannot tolerate water logging. Frost condition is a must for tea plants. So it is grown on the hill slopes.

Question 3.
Inundation canals are not dependable source of irrigation.
Answer:
Inundation canals are operational only during rainy season for the diversion of flood water directly from the rivers. Hence these canals are not dependable source of irrigation.

Question 4.
Shifting agriculture is also called as slash and burn agriculture.
Answer:
Once the forest land piece is cleared by tribal people they grow crops for two to three years and bum the stumps after harvest and abandoning the lands to regain its fertility and then move to new areas. Thus, shifting agriculture is also called ‘slash and bum’ agriculture.

Question 5.
Only little surplus is left in subsistence farming.
Answer:
Mainly in subsistence farming crops are grown for family consumption leaving little surplus to sell in the market. Preference will be given to food crops as per their needs.

Question 6.
Indian agriculture is mainly dominated by the food crops.
Answer:
As the population increases the need for food also increase. Due to the need and to supply to the large population Indian agriculture is mainly dominated by the food crops.

VII. Distinguish between the following

Question 1.
Laterite and Red soil.
Solution:
Laterite soil:

1. Femed by the process of leaching under wet and hot dry conditions.
2. Mainly composed of hydrated oxides of iron and aluminium.
3. Found mostly on hilly areas.
4. Suitable for tea, coffee, rubber and cashewnut.

Red soil:

1. Formed by the decomposition of ancient crystalline rocks.
2. Rich in minerals like iron and magnesium.
3. Found in plateau regions.
4. Suitable for pulses and sugarcane.

Question 2.
Arid and desert soil and Peaty and marshy soil.
Answer:
Arid and Desert soil:

1. Formed due to dry climate and high temperature.
2. Poor in organic matter and nitrogen rich in salt content.
3. Found in Rajasthan Northern Gujarat and Southern Punjab.
4. Millets, barley and pulses grow with irrigation.

Peaty and Marshy soil:

1. Formed in humid regions from organic matter.
2. Poor in potash and phosphate rich in vegetable organic matter.
3. Found in coastal areas and Sunderban Deltaic region, Kerala, Odisha, West Bengal.
4. Ideal for paddy and Jute cultivation.

Question 3.
Open well and Tube well irrigation.
Answer:
Open well irrigation:

1. Need sufficient ground water availability.
2. Practiced in areas of Ganga plains and river Deltaic regions.

Tube well irrigation:

1. Can be found in areas of low water table and soft geological subsurface.
2. Need sufficient water supply. Predominant in the states of Gujarat, Maharashtra, Madhya Pradesh and TamilNadu.

Question 4.
Bhakra Nangal and Hirakud project.
Answer:
Bhakra Nangal Project:

1. Constructed on the river Sutlej.
2. Highest gravity dam in the world.
3. Punjab, Haryana and Rajasthan states are benefitted.

Hirakud Project:

1. Constructed on the river Mahanadhi.
2. Longest dam in the world.
3. State of Odhisha is benefitted by this project.

Question 5.
Subsistence and Mixed farming.
Answer:
Subsistence farming:

1. Crops is mainly cultivated for family consumption.
2. Traditional farming methods are used due to small land holdings.
3. Mainly concentrated on food crops.

Mixed farming:

1. Integrated farming to satisfy many needs of the farmers.
2. Modem techniques is used for crop cultivation done in a vast area.
3. System include crop production along with raising live stock, poultry, fisheries, bee keeping etc.

Question 6.
Food and Cash crops.
Answer:
Food crops:

1. Mainly grown for consumption purpose.
2. Food crops include rice, wheat, pulses etc.
3. Apart from consumption used as raw materials for agro based industries.

Cash crops:

1. Crops are cultivated for commercial purpose.
2. Sugarcane, cotton, jute, oil seeds are the main cash crops. .
3. Mainly produced for raw materials for industries and earn valuable foreign exchange.

Question 7.
Rice and Wheat.
Answer:
Rice:

1. Mainly Tropical crop.
2. Need abundant supply of water till harvest.
3. West Bengal, Uttar Pradesh, Punjab, TamilNadu, Andhra Pradesh are some of the leading states in Rice production.

Wheat:

1. Sub tropical or Temperate crop.
2. Need moderate water supply.
3. Uttar Pradesh, Punjab, Haryana, Rajasthan and Madhya Pradesh are the leading states in wheat production.

VIII. Answer in a paragraph

Question 1.
What is a multipurpose project and explain its purpose?
Answer:
A comprehensive river valley project which serves a number of purposes simultaneously is called a “Multipurpose project”. Multipurpose projects serve the following purposes.

1. They help to store water, that can be utilised, when water, is in great demand both for agricultural and domestic purpose.
2. They check floods and famines.
3. Afforestation is undertaken in the catchment areas of river, which helps conservation of water, soil and wildlife. Thus it keeps ecosystem intact.
4. Production of hydro electricity is also another purpose of these projects. It is a pollution free of energy and is renewable energy.
5. They attract tourists and develops tourism industry.
6. Soil conservation and land relamation are other purpose of these projects.

Question 2.
What do you mean by Irrigation? Why it is necessary in India?
Answer:

1. Watering to agricultural lands by artificial means for cultivation is called Irrigation.
2. India is a tropical monsoon country.
3. 75% of rainfall is received within a span of four months.
4. Indian rainfall from monsoons are seasonal, uneven, irregular and erratic in nature.
5. So always there is a need for irrigation to carry out agricultural activities during dry period.
6. Besides erratic rainfall prevalence of high temperature, cultivation of annual crops and hydrophytes.
7. Commercial farming and porous soil make irrigation an essential one for agriculture in India.

Question 3.
What are the different sources of irrigation used in different parts of India?
Answer:
The main sources of irrigations are
1. Canal irrigation
2. Well irrigation
3. Tank irrigation

1. Canal irrigation:
It is the second most important sources of irrigation in India. The Canals are of two types.
i. Inundation canals
ii. Perennial canals

i. Inundation canals:
In this, water is taken directly from the rivers without making any kind of barrage or dam. Such canals are useful for the diversion of flood water from the rivers and remains operational during rainy season.

ii. Perennial canals:
These are developed from perennial work by constructing barrage to regulate the flow of water. These canals are useful for irrigation.

2. Well irrigation:
A Well is a hole or trough usually vertical excavated in the earth for brining groundwater to the surface. It contributes about 62% of net irrigated area in India. Wells are of two types.
i. Open well
ii. Tube well

i. Open well:
This type of irrigation is widely practiced in the areas where groundwater is sufficiently available. The areas are in Ganga plains, the deltaic region of Mahanadi, Godavari, Krishna, Cauvery and parts of Narmada and Tapti valleys.

ii. Tube well:
Tube wells are developed in the areas of low water table, sufficient power supply and soft subsurface geological units. Tube wells are predominant in the states of Gujarat, Maharashtra, Punjab, MP, and Tamil Nadu.

3. Tank irrigation:
A tank is a natural or man-made hollow on the surface developed by constructing a small bund around it across a stream It is used to collect and store water for irrigation and other purpose. It also includes irrigation from taken and ponds.

Question 4.
How is Live-stock census conducted in TamilNadu?
Answer:
State Government is conducting Live stock census with the help of:

1. Department of Animal Husbandary at State level and
2. Regional Joint Director at District level under the guidelines of Government of India ministry of Agriculture and farmers welfare,
3. Department of Animal husbandary, Dairying and Fisheries conducted once in 5 years.

Question 5.
Explain about the major issues faced by the Indian farmers?
Answer:
We can divide the problems faced by the Indian agriculture and by the farmers into two Natural and Man made.
Natural problems:

1. Soil erosion: Large tracts of land suffer from soil erosion by wind and water.
2. Infertile soil: Growing crops for many years without replenishing led to the exhaution of soil and its depletion.
3. Lack of Irrigation: Only some areas of the cropped falls under irrigation.

Man made problems:

1. Small land holdings and fragmented land: Poor status made the farmers to have small land and also some farmers possesses share from their ancestral property cannot afford to apply mechanism.
2. High costs of Inputs: Good quality of seeds are out of reach for many small and marginal farmers due to their high price.
3. Agricultural marketing: Absence of sound marketing, facility, interference of local traders and middlemen for the disposal of their produce, fluctuations in the price.
4. In adequate transport: Lakhs of villages are not w7ell connected with main roads or with market centres. Lack of cheap and efficient means of transportation is not available.
5. Scarcity of capital: Huge capital is needed to purchase advanced farm machineries and equipments which the poor farmers cannot afford to buy.

Question 6.
List out some of the Agricultural Revolutions in India.
Answer:

Question 7.
“Per Drop more Crop”. Explain this statement.
Answer:

1. It is the scheme introduced by the Government of India with the objective to enhance water use efficiency.
2. This micro irrigation scheme comes under “Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) and centrally sponsored scheme on micro irrigation.
3. It promotes appropriate technological interventions like drop and sprinkler irrigation technologies in agriculture and encourage farmers to use water saving and conservation technique.
4. Following five states progressed 78% under micro irrigation scheme
   • Andhra Pradesh
   • Karnataka
   • Gujarat
   • Maharashtra
   • TamilNadu

IX. Map Questions
Mark the following on the outline map of India.

Question 1.
Areas of Red soil and Mountain soil.
Answer:

Question 2.
Demarcate the states producing the highest for the following crops.
Answer:
(i) Paddy

(ii) Sugarcane

(iii) Cotton

(iv) Wheat

Question 3.
Kosi project, Tungabadra, Periyar Dam, Nagarjuna Sagar.
Answer:

Students can download 10th Science Chapter 7 Atoms and Molecules Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 7 Atoms and Molecules

Samacheer Kalvi 10th Science Atoms and Molecules Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
Which of the following has the smallest mass?
(a) 6.023 × 10²³ atoms of He
(b) 1 atom of He
(c) 2 g of He
(d) 1-mole atoms of He
Answer:
(b) 1 atom of He

Question 2.
Which of the following is a triatomic molecule?
(a) Glucose
(b) Helium
(c) Carbon dioxide
(d) Hydrogen.
Answer:
(c) Carbon dioxide
Hint:
(a) Glucose = C₆H₁₂O₆ (Polyatomic molecule)
(b) Helium = He (Monoatomic molecule)
(c) Carbon dioxide = CO₂ (Triatomic molecule)
(d) Hydrogen = H₂ (Diatomic molecule)
So, (c) is the correct answer.

Question 3.
The volume occupied by 4.4 g of CO₂ at S.T.P:
(a) 22.4 litre
(b) 2.24 litre
(c) 0.24 litre
(d) 0.1 litre
Answer:
(b) 2.24 litre

Question 4.
Mass of 1 mole of Nitrogen atom is _____.
(a) 28 amu
(b) 14 amu
(c) 28 g
(d) 14 g.
Answer:
(b) 14 amu
Hint: Atomic mass of Nitrogen is 14.00674 grams. It is equal to 1 mole of Nitrogen atoms.
So, answer (b) is correct.

Question 5.
Which of the following represents 1 amu?
(a) Mass of a C – 12 atom
(b) Mass of a hydrogen atom
(c) 1/12 th of the mass of a C – 12 atom
(d) Mass of O – 16 atom
Answer:
(c) 1/12 th of the mass of a C – 12 atom

Question 6.
Which of the following statement is incorrect?
(a) One gram of C – 12 contains Avogadro’s number of atoms.
(b) One mole of oxygen gas contains Avogadro’s number of molecules.
(c) One mole of hydrogen gas contains Avogadro’s number of atoms.
(d) One mole of electrons stands for 6.023 × 10²³ electrons.
Answer:
(a) One gram of C – 12 contains Avogadro’s number of atoms.
Hint: 12 g of Carbon contains 6.023 × 10²³ atoms,
1 g of Carbon contain \(\frac{6.023 \times 10^{23}}{12}\) = 5.018 × 10²² atoms and its is not Avogadro’s number of atoms.
So (a) is the incorrect statement.

Question 7.
The volume occupied by 1 mole of a diatomic gas at S.T.P is:
(a) 11.2 litre
(b) 5.6 litre
(c) 22.4 litre
(d) 44.8 litre
Answer:
(c) 22.4 litre

Question 8.
In the nucleus of ₂₀Ca⁴⁰, there are
(a) 20 protons and 40 neutrons
(b) 20 protons and 20 neutrons
(c) 20 protons and 40 electrons
(d) 40 protons and 20 electrons
Answer:
(b) 20 protons and 20 neutrons

Question 9.
The gram molecular mass of oxygen molecule is_____.
(a) 16 g
(b) 18 g
(c) 32 g
(d) 17 g.
Answer:
(c) 32 g
Hint: By definition, the gram molecular mass of oxygen molecule O₂ is 32 g.
So the answer (c) is correct.

Question 10.
1 mole of any substance contains molecules.
(a) 6.023 × 10²³
(b) 6.023 × 10^-23
(c) 3.0115 × 10²³
(d) 12.046 × 10²³
Answer:
(a) 6.023 × 10²³

II. Fill in the blanks:

1. Atoms of different elements having ……… mass number, but ………. atomic numbers are called isobars.
2. Atoms of different elements having same number of ………. are called isotones.
3. Atoms of one element can be transmuted into atoms of other element by ………….
4. The sum of the numbers of protons and neutrons of an atom is called its …………
5. Relative atomic mass is otherwise known as …………
6. The average atomic mass of hydrogen is ……….. amu.
7. If a molecule is made of similar kind of atoms, then it is called ……….. atomic molecule.
8. The number of atoms present in a molecule is called its ………….
9. One mole of any gas occupies ………… ml at S.T.P
10. Atomicity of phosphorous is …………
Answer:
1. same, different
2. neutrons
3. artificial transmutation
4. mass number
5. standard atomic weight
6. 1.008
7. homo
8. atomicity
9. 22, 400
10. four

III. Match the following:

Answer:
A. (ii)
B. (iii)
C. (v)
D. (i)
E. (iv)

IV. True or False: (If false give the correct statement)

1. Two elements sometimes can form more than one compound.
2. Nobel gases are diatomic.
3. The gram atomic mass of an element has no unit.
4. 1 mole of Gold and Silver contain same number of atoms.
5. Molar mass of CO₂ is 42 g.

Answer:

1. True
2. False – Noble gases are Monoatomic.
3. False – The unit of gram atomic mass of an element is gram.
4. True
5. False – Molar mass of CO₂ is 44 g.

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: Atomic mass of aluminium is 27
Reason: An atom of aluminium is 27 times heavier than 1/12 th of the mass of the C-12 atom.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: The Relative Molecular Mass of Chlorine is 35.5 a.m.u.
Reason: The natural abundance of Chlorine isotopes are not equal.
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(c) Assertion is wrong, Reason is correct.

VI. Short answer questions:

Question 1.
Define: Relative atomic mass.
Answer:
Relative atomic mass of an element is the ratio between the average mass of its isotopes to \(\frac{1}{12^{th}}\)part of the mass of a carbon-12 atom. It is denoted as A_r.
[OR]

Question 2.
Write the different types of isotopes of oxygen and its percentage abundance.
Answer:
Oxygen has three stable isotopes. They are

Question 3.
Define Atomicity.
Answer:
The number of atoms present in the molecule is called its ‘Atomicity’.

Question 4.
Give any two examples for heteroatomic molecules.
Answer:
HI, HCl, CO, HBr, HF.

Question 5.
What is Molar volume of a gas?
Answer:
One mole of any gas occupies 22.4 litres.
(or)
22400 ml at S.T.R This volume is called as molar volume.

Question 6.
Find the percentage of nitrogen in ammonia.
Answer:
Molar mass of NH₃ = 1(14) + 3(1) = 17 g

VII. Long answer questions:

Question 1.
Calculate the number of water molecule present in one drop of water which weighs 0.18 g.
Answer:
The molecular mass of water (H₂O) is 18.
18 g of water molecule = 1 mole.
0. 18 g of water = \(\frac{1}{18} \times 0.18\) = 0.01 mole.
1 mole of water (Avogadro’s number) contains 6.023 × 10²³ water molecules.
0. 01 mole of water contain \(\frac{6.023 \times 10^{23}}{1} \times 0.01\) = 6.023 × 10²¹ molecules.

Question 2.
N₂ + 3 H₂ → 2 NH₃
(The atomic mass of nitrogen is 14, and that of hydrogen is 1)
1 mole of nitrogen (……..g) +
3 moles of hydrogen (………g) →
2 moles of ammonia (………g)
Answer:
1 mole of nitrogen (28 g) +
3 moles of hydrogen (6 g) →
2 moles of ammonia (34 g)

Question 3.
Calculate the number of moles in
(i) 27 g of Al;
(ii) 1.51 × 10²³ molecules of NH₄Cl.
Answer:
(i) 27 g of Al
Given mass atomic mass = \(\frac{Given Mass}{Atomic Mass}\) = \(\frac{27}{27}\)
= 1 mole

(ii) 1.51 x 10²³ molecules of NH₄Cl
Number of moles

Question 4.
Give the salient features of “Modern atomic theory”.
Answer:
The salient features of “Modem atomic theory” are,

1. An atom is no longer indivisible.
2. Atoms of the same element may have different atomic mass.
3. Atoms of different elements may have the same atomic masses.
4. Atoms of one element can be transmuted into atoms of other elements. In other words, an atom is no longer indestructible.
5. Atoms may not always combine in a simple whole-number ratio.
6. Atom is the smallest particle that takes part in a chemical reaction.
7. The mass of an atom can be converted into energy [E = mc²].

Question 5.
Derive the relationship between Relative molecular mass and Vapour density.
Answer:
Relative molecular mass : The relative molecular mass of a gas or vapour is the ratio between the mass of one molecule of the gas or vapour to mass of one atom of hydrogen.
Vapour density : Vapour density is the ratio of the mass of certain volume of a gas or vapour, to the mass of an equal volume of hydrogen, measured under the same conditions of temperature and pressure.

According to Avogadro’s law equal volumes of all gases contain equal number of molecules.
Let the number of molecules in one volume = n, then

When cancelling ‘n’ which is common at STP, we get

Since hydrogen is diatomic,

2 × Vapour density = Relative Molecular mass of a gas
[OR]
Relative Molecular Mass = 2 × Vapour density

VIII. HOT Question:

Question 1.
Calcium carbonate is decomposed on heating in the following reaction
CaCO₃ → CaO + CO₂

1. How many moles of Calcium carbonate is involved in this reaction?
2. Calculate the gram molecular mass of calcium carbonate involved in this reaction.
3. How many moles of CO₂ are there in this equation?

Answer:
CaCO₃ → CaO + CO₂

1. 1 mole of CaCO₃ is involved in this reaction.
2. Gram molecular mass of calcium carbonate
   CaCO₃ = (40 + 12 + 3 × 16) = 52 + 48 = 100 g
3. 1 mole of CO₂ is in this equation.

IX. Solve the following problems:

Question 1.
How many grams are there in the following?
(i) 2 moles of a hydrogen molecule, H₂
(ii) 3 moles of chlorine molecule, Cl₂
(iii) 5 moles of sulphur molecule, S₈
(iv) 4 moles of a phosphorous molecule, P₄
Solution:
(i) 2 moles of a hydrogen molecule, H₂
Mass of 1 mole of hydrogen molecule = 2 g
Mass of 2 moles of hydrogen molecule = 2 × 2 = 4 g.

(ii) 3 moles of chlorine molecule, Cl₂
Mass of 1 mole of chlorine molecule = 71 g
Mass of 3 moles of chlorine molecules = 71 × 3 = 213 g.

(iii) 5 moles of sulphur molecule, S₈
Mass of 1 mole of sulphur molecule = 32 g
Mass of 5 moles of sulphur molecules = 32 × 5 = 160 g.

(iv) 4 moles of the phosphorous molecule, P₄
Mass of 1 mole of phosphorous molecule = 30.97 g
Mass of 4 moles of phosphorous molecules = 30.97 × 4 = 123.88 g.

Question 2.
Calculate the % of each element in calcium carbonate. (Atomic mass: C – 12, O – 16, Ca – 40)
Answer:
Formula to find % of each element

Question 3.
Calculate the % of oxygen in Al₂(SO₄)₃.
(Atomic mass: Al – 27, O – 16, S – 32)
Answer:
Formula:

Molar mass of Al₂(SO₄)₃ = [2(Atomic mass of Al) + 3(Atomic mass of S) + 12(Atomic mass of O)]
= 2(27) + 3(32) + 12(16) = 342 g
% of Oxygen = \(\frac{12(16)}{342}\) × 100 = 56.14%.

Question 4.
Calculate the % relative abundance of B – 10 and B – 11, if its average atomic mass is 10.804 amu.
Answer:
% of relative abundance can be calculated by the formula.
Average atomic mass of the element
= Atomic mass of 1st isotope × abundance of 1st isotope + Atomic mass of 2nd isotope × abundance of 2nd isotope
∴ Average atomic mass of Boron
= Atomic mass of B – 0 × abundance of B -10 + Atomic mass of B – 11 × abundance of B – 11
Let the abundance of B – 10 be ‘x’ and B – 11 be (1 – x)
So, 10.804 = 10 × x + 11 (1 – x)
10.804 = 10x + 11 – 11x
x = 11 – 10.804
x = 0.196
1 -x = 1 – 0.196 = 0.804
Therefore % abundance of B – 10 is 19.6% and B – 11 is 80.4%
[OR]
Let the % of the isotope B – 10 = x
Then the % of the isotope B – 11 = 100 – x

1100 – x = 1080.4
x = 19.6
% abundance of B – 10 = 19.6%
% abundance of B – 11 = 80.4%

Samacheer Kalvi 10th Science Atoms and Molecules Additional Important Questions and Answers

I. Choose the correct answer.

Question 1.
The first scientific theory of an atom was proposed by:
(a) Ruther Ford
(b) Newland
(c) John Dalton
(d) Neils Bohr
Answer:
(c) John Dalton

Question 2.
Identify the pair that indicates isobars among the following _____.
(a) \(_{1} \mathrm{H}^{2},_{1} \mathrm{H}^{3}\)
(b) \(_{17} \mathrm{Cl}^{35},_{17} \mathrm{Cl}^{37}\)
(c) \(\text { (c) }_{18} \mathrm{Ar}^{40},_{18} \mathrm{Ca}^{40}\)
(d) \(_{6} \mathrm{C}^{13},_{7} \mathrm{N}^{14}\).
Answer:
(c) \(\text { (c) }_{18} \mathrm{Ar}^{40},_{18} \mathrm{Ca}^{40}\)

Question 3.
Which one of the following represents 180 g of water?
(a) 5 moles of water
(b) 90 moles of water
(c) 6.023 × 10²⁴ molecules of water
(d) 6.023 × 10²² molecules of water
Answer:
(c) 6.023 × 10²⁴ molecules of water

Question 4.
The isotope of Carbon-12 contains _____.
(a) 6 protons and 7 electrons
(b) 6 protons and 6 neutrons
(c) 12 protons and no neutrons
(d) 12 neutrons and no protons.
Answer:
(b) 6 protons and 6 neutrons

Question 5.
Which contains the greatest number of moles of oxygen atoms?
(a) 1 mol of water
(b) 1 mole of NaOH
(c) 1 mole of Na₂CO₃
(d) 1 mole of CO
Answer:
(c) 1 mole of Na₂CO₃

Question 6.
The mass of proton or neutron is approximately _____.
(a) 1 amu
(b) 1.609 × 10^-19 g
(c) 1 g
(d) 6.023 × 10^-23 g.
Answer:
(a) 1 amu

Question 7.
The natural abundance of C-12 and C-13 are 98.90% and 1.10% respectively. The average atomic mass of carbon is:
(a) 12 amu
(b) 12.011 amu
(c) 14 amu
(d) 12.90 amu
Answer:
(b) 12.011 amu

Question 8.
The relative atomic mass of magnesium-based on C – 12 scale is _____.
(a) 24 g
(b) 24
(c) 24 amu
(d) 24 kg
Answer:
(b) 24

Question 9.
If 1.5 moles of oxygen combine with Al to form Al₂O₃, the mass of Al in g (atomic mass of Al = 27) used in the reaction is:
(a) 2.7
(b) 54
(c) 40.5
(d) 81
Answer:
(b) 54

Question 10.
The atomicity of methane is:
(a) 5
(b) 4
(c) 3
(d) 6
Answer:
(a) 5

Question 11.
Find the odd one out _____.
(a) \(_{8} \mathrm{O}^{16}\)
(b) \(_{8} \mathrm{O}^{17}\)
(c) \(_{6} \mathrm{O}^{12}\)
(d) \(_{8} \mathrm{O}^{18}\).
Answer:
(c) \(_{6} \mathrm{O}^{12}\)

Question 12.
The volume occupied by 3 moles of HCl gas at STP is:
(a) 22.4 L
(b) 44.8 L
(c) 2.24 L
(d) 67.2 L
Answer:
(d) 67.2 L

Question 13.
The mass percentage of hydrogen in ethane (C₂H₆) is:
(a) 25%
(b) 75%
(c) 80%
(d) 20%
Answer:
(d) 20%

Question 14.
Which one of the following is a homo diatomic molecule?
(a) H₂
(6) CO
(c) NO
(d) O₃.
Answer:
(a) H₂

Question 15.
The percentage of nitrogen in urea is about:
(a) 38.4
(b) 46.6
(c) 59.1
(d) 61.3
Answer:
(b) 46.6

Question 16.
Out of the following the largest number of atoms are contained in:
(a) 11 g of CO₂
(b) 4 g of H₂
(C) 5 g of NH₃
(d) 8 g of SO₂
Answer:
(b) 4 g of H₂

Question 17.
Which of the following is an example of a homo triatomic molecule?
(a) Phosphorous
(b) Sulphur
(c) Bromine
(d) Ozone.
Answer:
(d) Ozone.

Question 18.
For the reaction A + 2B → C, 5 moles of A and 8 moles of B will produce:
(a) 5 moles of C
(b) 4 moles of C
(c) 8 moles of C
(d) 13 moles of C
Answer:
(b) 4 moles of C

Question 19.
The vapour density of a gas is 32. Its relative molecular mass will be:
(a) 32
(b) 16
(c) 64
(d) 96
Answer:
(c) 64

Question 20.
Find the odd one out _____.
(a) Silver
(b) Potassium
(c) Iron
(d) Phosphorous.
Answer:
(d) Phosphorous.

II. Fill in the blanks.

1. The volume occupied by 16 g of oxygen is ………..
2. One mole of a triatomic gas contains ………… atoms.
3. Equal volume of all gases under the same conditions of temperature and pressure contain equal number of …………
4. The mass of an atom can be converted into energy by using the formula …………
5. The percentage composition is useful to determine the ………… formula and ………… formula.

Answer:

1. 11.2 L
2. 3 × 6.023 × 10²³
3. molecules
4. E = me²
5. empirical, molecular

III. Match the following:

Question 1.
Match the Column I with Column II.

Answer:
A. (ii)
B. (iii)
C. (i)
D. (v)
E. (iv)

Question 2.
Match the Column I with Column II.

Answer:
A. (iii)
B. (i)
C. (iv)
D. (v)
E. (ii)

Question 3.
Match the Column I with Column II.

Answer:
A. (iv)
B. (v)
C. (ii)
D. (iii)
E. (i)

Question 4.
Match the Column I with Column II.

Answer:
A. (v)
B. (iii)
C. (iv)
D. (i)
E. (ii)

IV. True or False: (If false give the correct statement)

1. Atoms always combine in a simple whole number ratio.
2. 2 × RMM = VD
3. The average atomic mass of Beryllium is 9.012 because of the presence of isotopes.
4. The noble gases are diatomic.
5. The number of atoms present in one mole of phosphorus(P₄) is 4 × 6.023 × 10²³

Answer:

1. False -Atoms may not combine always in a simple whole number ratio.
2. False – 2 × VD = RMM
3. True
4. False – The noble gases are mono atomic.
5. True

V. Assertion and Reason:

Answer the following questions using the data given below:
Question 1.
Assertion: The standard unit for expressing mass of atom is amu.
Reason: Atomic mass unit is one-twelth of the mass of a C-12 atom
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

Question 2.
Assertion: The volume occupied by 44 g of CO₂ is 22.4 L
Reason: The volume occupied by one mole of any gas is 22.4 L
(a) Assertion and Reason are correct, Reason explains the Assertion.
(b) Assertion is correct, Reason is wrong.
(c) Assertion is wrong, Reason is correct.
(d) Assertion and Reason are correct, Reason doesn’t explains Assertion.
Answer:
(a) Assertion and Reason are correct, Reason explains the Assertion.

VI. Short answer questions:

Question 1.
Define vapour density.
Answer:
Vapour density is the ratio of the mass of certain volume of a gas or vapour, to the mass of an equal volume of hydrogen measured under the same condition of temperature and pressure.
[OR]

Question 2.
What are isobars? Give an example.
Answer:
Atoms of different elements that have same atomic masses but different atomic numbers are called isobars.
e.g., \(_{18} \mathrm{Ar}^{40}\), \(_{20} \mathrm{Ca}^{40}\).

Question 3.
Write the differences between an atom and a molecule.
Answer:

Question 4.
What is artificial transmutation?
Answer:
Atoms of one element can be transmuted into atoms of other elements. In other words, the atom is no longer indestructible. It is known as artificial transmutation.

Question 5.
Classify the following based on atomicity.
Answer:
(i) Bromine
2 – Diatomic

(ii) Argon
1 – Monoatomic

(iii) Ozone
3 – Triatomic

(iv) Sulphur
8 – Polyatomic

Question 6.
Define atomic mass unit.
Answer:
Atomic mass unit is one-twelfth of the mass of carbon – 12 atom, as an isotope of carbon which contains 6 protons and 6 neutrons. It is amu.

VII. Long answer questions:

Question 1.
Explain how Avogadro hypothesis is used to derive the value of atomicity.
Answer:
(i) The Avogadro’s law states that “equal volumes of all gases under similar conditions of temperature and pressure contain the equal number of molecules”.

(ii) Let us consider the reaction between hydrogen and chlorine to form hydrogen chloride gas.
H_{2 (g)} + Cl_{2 (g)} → 2HCl _(g)
⇒ 1 volume + 1 volume → 2 volumes.

(iii) According to Avogadro’s law, 1 volume of any gas is occupied by “n” number of molecules,
“n” molecules + “n” molecules → “2n” molecules
If “n” = 1, then
1 molecule + 1 molecule → 2 molecules.
\(\frac { 1 }{ 2 }\) molecule + \(\frac { 1 }{ 2 }\) molecule → 1 molecule.

(iv) 1 molecule of hydrogen chloride gas is made up of \(\frac { 1 }{ 2 }\) molecule of hydrogen and \(\frac { 1 }{ 2 }\) molecule of chlorine.

(v) \(\frac { 1 }{ 2 }\) molecule of hydrogen contains 1 atom.
So, 1 molecule of hydrogen contains 2 atoms.
So, hydrogen atomicity is 2. Similarly, chlorine atomicity is also 2.
So, H₂ and Cl₂ are diatomic molecules.

Question 2.
Write a note on the following,
(i) Isotopeos
(ii) Isobars
(iii) Relative atomic mass.
Answer:
(i) Isotopes : Atoms of same element with different mass number. Eg: ₁₇Cl³⁵, ₁₇Cl³⁷.
(ii) Isobars : Atoms of different elements with same mass number. Eg: ₁₈Ar⁴⁰, ₂₀Ca⁴⁰
(iii) Relative Atomic Mass (RAM) :

Question 3.
Sodim bicarbonate breaks down on heating as follows:
2NaHCO₃ → Na₂CO₃ + H₂O + CO₂
(Atomic mass of Na = 23, H = 1, C = 12, O = 16)
(i) How many moles of NaHCO₃ are there in the equation?
Answer:
2 moles.

(ii) What is the mass of CO₂ produced in the equation?
Answer:
44 g

(iii) How many moles of water molecules are produced in the equation?
Answer:
1 mole.

(iv) What is the mass of NaHCO₃ used in this equation?
Answer:
= 2[23 + 1 + 12 + 3(16)]
= 2[84]
= 168 g

(v) What is the volume occupied by CO₂ in this equation?
Answer:
22.4 lit.

VIII. Hot Questions

Question 1.
Why do we take an atomic mass of Carbon – 12 as standard?
Answer:
Carbon – 12 is the standard while measuring the atomic masses. Because no other nuclides other than C – 12 have exactly whole-number masses in this scale. This is due to the different mass of neutrons and protons acting to change the total mass in nuclides with proton/neutron ratio other than 1 : 1 ratio of carbon – 12.

Question 2.
The cost of common salt (NaCl) is Rs 18 per kg. Calculate the cost of the salt per mole.
Answer:
Gram molar mass of NaCl = 23 + 35.5
= 58.5 g
1000 g of NaCl costs = Rs 18
∴ 58.5 g of NaCl costs = \(\frac{18}{1000}\) × 58.5
= Rs 1.053
The cost of one mole of NaCl = Rs 1.053

Question 3.
What will be the mass of one \(^{12} \mathbf{C}\) atom in g?
Answer:
1 mol of \(^{12} \mathbf{C}\) atoms = 6.022 × 10²³ atoms = 12 g
Thus, 6.022 × 10²³ atoms of \(^{12} \mathbf{C}\) have mass = 12 g
∴ 1 atom of \(^{12} \mathbf{C}\) will have mass = \(\frac{12}{6.022 \times 10^{23}}\) g = 1.9927 × 10^-23 g.

IX. Solve the following problems:

Question 1.
Calculate the average atomic mass of carbon, if the natural abundance of C – 12 and C – 13 are 98.90% and 1.10% respectively.
Solution:
Average atomic mass of carbon
\(=\left(12 \times \frac{98.9}{100}\right)+\left(13 \times \frac{1.1}{100}\right)\)
= (12 × 0.989) +(13 × 0.011)
= 11.868 + 0.143
= 12.011 amu.

Question 2.
Find how many moles are there in
(a) 98 g of H₂SO₄
Answer:
(a) 98 g of H₂SO₄
GMM of H₂SO₄ = 2(1) + 32 + 4(16)
= 98 g
Number of moles = \(\frac{Given Mass}{Mol. Mass}\)
= \(\frac{98}{98}\)
= 1 mole

(b) 18.069 × 10²³ atoms of calcium
Answer:
Number of moles

= 3 moles

(c) 4.48 L of CO₂
Answer:
Number of moles

Question 3.
Calculate the number of moles in
(i) 12.046 × 10²³ atoms of copper
(ii) 27.95 g of iron
(iii) 1.51 × 10²³ molecules of CO₂
Answer:
(i) 12.046 × 10²³ atoms of copper
6.023 × 10²³ atoms of copper = 1 mole
12.046 × 10²³ atoms of copper = \(\frac{1 \times 12.046 \times 10^{23}}{6.023 \times 10^{23}}\) = 2 moles of copper

(ii) 27.95 g of iron
55.9 g of iron = 1 mole
27.95 g of iron = \(\frac{1}{55.9}\) × 27.95 = 0.5 mole of iron.

(iii) 1.51 × 10²³ molecules of CO₂
No of moles = \(\frac{\text { No. of molecules }}{\text { Avogadro number }}\)
= \(\frac{1.51 \times 10^{23}}{6.023 \times 10^{23}}\)
= 0.25 mole of CO₂

Question 4.
Calculate the number of atoms of mercury present in 1 kg of Mercury. [Atomic mass of Hg = 200.6]
Answer:
200.6 g of Hg contains 6.023 × 10²³ Hg atoms
∴ 1 Kg of Hg will contain = \(\frac{6.023×10^{23}}{200.6}\) × 1000
= 30.02 × 10²³ Hg atoms

Question 5.
How many molecules are present in 7 × 10^-3 m³ of NH₃ at STP?
Answer:
Molar volume = 22.4 dm³ = 2.24 × 10^-2 m³
2.24 × 10^-2 m³ of NH₃ at STP contains 6.023 × 10²³ NH₃ molecules.
:. 7 × 10^-3 m³ of NH₃ will contain
= \(\frac{6.023×10^{23}}{2.24×10^{-2}}\) × 7 × 10^-3
18.82 × 10²² NH₃ molecule

Question 6.
What is the mass in grams of the following?
(a) 3 moles of NaOH
(b) 6.023 × 10²² atoms of Ca
(c) 224 L of CO₂
Answer:
Formula:

(a) 3 moles of NaOH
Mass of 3 moles of NaOH = 3 × mol. mass of NaOH
GMM of NaOH = 23 + 16 + 1 = 40 g
Mass of 3 moles of NaOH = 3 × 40 = 120 g

(b) 6.023 × 10²² atoms of Ca = n × atomic mass of ca

= 4 g

(c) 224 L of CO₂
Mass of 224 L of CO₂

= 10 × 44
= 440 g

Question 7.
How many grams are therein:
(i) 5 moles of water
(ii) 2 moles of Ammonia
(iii) 2 moles of Glucose
Solution:
(i) 5 moles of water.
Mass of 1 mole of water (H₂O) = 18 g (2 + 16)
Mass of 5 moles of H₂O = 18 × 5 = 90 g.

(ii) 2 moles of ammonia.
Mass of 1 mole of ammonia (NH₃) = 17 g (14 + 3)
Mass of 2 moles of ammonia = 17 × 2 = 34 g.

(iii) 2 moles of glucose.
Mass of 1 mole of glucose (C₆H₁₂O₆) = 180 g (72 + 12 + 96)
Mass of 2 moles of glucose = 180 × 2 = 360 g.

Question 8.
Calculate tbe molar mass of the following compounds.
(a) Urea (NH₂CONH₂)
(b) Ethanol(C₂H₅OH);
(c) Boric acid (H₃BO₃)
[Atomic mass of N – 14, H – 1, C – 12, B – 11, O – 16]
Answer:
(a) Urea (NH₂CONH₂) = 2(14) + 4(1) + 1(16) + 1(12)
= 28 + 4 + 16 + 12
= 60 g

(b) Ethanol(C₂H₅OH) = 2(12) + 6(1) + 1(16)
= 24 + 6 + 16 = 46 g

(c) Boric acid (H₂BO₃) = 3(1) + 1(11) + 3(16)
= 3 + 11 + 48
= 62 g

Question 9.
Mass of one atom of an element is 6.645 × 10^-23 g. How many moles of element are there in 0.320 kg.
Answer:
Mass of one atom of an element = 6.645 × 10^-23 g
∴ Mass of 1 mol of atom = 6.645 × 10^-23 × 6.023 × 10²³ = 40 g
Number of moles =

Students can download 10th Social Science Geography Chapter 2 Climate and Natural Vegetation of India Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 2 Climate and Natural Vegetation of India

Samacheer Kalvi 10th Social Science Climate and Natural Vegetation of India Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
Meteorology is the science of:
(a) Weather
(b) Social
(c) Political
(d) Human
Answer:
(a) Weather

Question 2.
We wear cotton during ……….
(a) Summer
(b) Winter
(c) Rainy
(d) Northeast monsoon
Answer:
(a) Summer

Question 3.
Western disturbances cause rainfall in:
(a) Tamilnadu
(b) Kerala
(c) Punjab
(d) Madhya Pradesh
Answer:
(c) Punjab

Question 4.
………. helps in quick ripening of mangoes along the coast of Kerala and Karnataka.
(a) Loo
(b) Norwester
(c) Mango showers
(d) Jet stream
Answer:
(c) Mango showers

Question 5.
……………. is a line joining the places of equal rainfall.
(a) Isohyets
(b) Isobar
(c) Isotherm
(d) Latitudes
Answer:
(a) Isohyets

Question 6.
The climate of India is labelled as ………
(a) Tropical humid
(b) Equatorial Climate
(c) Tropical Monsoon Climate
(d) Temperate Climate
Answer:
(c) Tropical Monsoon Climate

Question 7.
The monsoon forests are otherwise called as
(a) Tropical evergreen forest
(b) Deciduous forest
(c) Mangrove forest
(d) Mountain forest
Answer:
(b) Deciduous forest

Question 8.
……. forests are found above 2400 m Himalayas.
(a) Deciduous forests
(b) Alpine forests
(c) Mangrove forests
(d) Tidal forests
Answer:
(b) Alpine forests

Question 9.
Sesahachalam hills, a Biosphere reserve is situated in
(a) Tamil Nadu
(b) Andhra Pradesh
(c) Madhya Pradesh
(d) Karnataka
Answer:
(b) Andhra Pradesh

Question 10.
………… is a part of the world network biosphere reserves of UNESCO .
(a) Nilgiri
(b) Agasthiyamalai
(c) Great Nicobar
(d) Kachch
Answer:
(a) Nilgiri

II. Match the following

Answer:
A. (iv)
B. (v)
C. (ii)
D. (i)
E. (iii)

III. Consider the given statements and choose the correct option from the given below ones.

Question 1.
Assertion(A): Monsoons are a complex meteorological phenomenon. Reason(R): Meteorologists have developed a number of concepts about the origin of monsoons.
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A.
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(a) Both (A) and (R) are true: R explains A

Question 2.
Assertion(A): The Himalayas acts as a climatic barrier.
Reason(R): The Himalayas prevents cold winds from central Asia and keep the Indian Sub-continent warm.(Give option for this questions)
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A.
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(a) Both (A) and (R) are true: R explains A

IV. Choose the inappropriate answer

Question 1.
Tidal forests are found in and around ……..
(a) Desert
(b) The deltas of Ganga and Brahmaputra
(c) The delta of Godavari
(d) The delta of Mahanadhi
Answer:
(a) Desert

Question 2.
Climate of India is affected by:
(a) Latitudinal extent
(b) Altitude
(c) Distance from the sea
(d) Soil
Answer:
(d) Soil

V. Answer briefly

Question 1.
Define ‘Meteorology’.
Answer:
The branch of science concerned with the processes and phenomena of the atmosphere, especially as a means of forecasting the weather.

Question 2.
What is meant by ‘normal lapse rate’?
Answer:
Temperature decreases when the altitude increases .Normal Lapse rate is a phenomenon in which temperature decreases at the rate of 6.5°C for every 1000mts of ascent. Hence places in the mountains are cooler than the places on the plain.

Question 3.
What are ‘jet streams’?
Answer:
In the upper layers of the atmosphere, there are strong westerly winds concentrated in a relatively narrow and shallow stream known as “Jet streams” They cause heavy rainfall in North-west India.

Question 4.
Write a short note on ‘Monsoon wind’.
Answer:

1. The Word ‘Monsoon’ is derived from the Arabic word “Mausim” which means season.
2. Monsoons are a complex meteorological phenomenon .
3. These winds originates due to the seasonal migration of planetary winds and pressure belts following the position of the sun.
4. During summer they blow from South west to North east ( South West monsoon) June-September and from the North east to South west (North East monsoon) October and November.

Question 5.
Name the four distinct seasons of India.
Answer:

1. Winter or cold weather season (Jan-Feb)
2. Pre Monsoon or Summer (March-May)
3. Southwest Monsoon or rainy season (June-September)
4. Northeast Monsoon season (October-December)

Question 6.
What is ‘burst of monsoon’?
Answer:

1. Prior to the onset of the Southwest monsoon the temperature in North India reaches up to 46°C.
2. The sudden approach of monsoon wind over South India with lightning and thunder is termed as the “break or burst of monsoon”.

Question 7.
Name the areas which receive heavy rainfall.
Answer:

1. Middle Ganga Valley
2. Western Ghats
3. Eastern Maharashtra
4. Madhya Pradesh and Odisha

Question 8.
State places of mangrove forest in India.
Answer:

1. Mangrove forests occur in and around the deltas, estuaries and creeks prone to tidal influences.
2. In India they are found in deltas of Ganga, Brahmaputra (largest), the deltas of Mahanadi, Godavari and Krishna rivers.

Question 9.
Name the trees of tropical evergreen forest.
Answer:
The most important trees are rubber, mahogany, ebony, rosewood, coconut, bamboo, cinchona, candes, palm, iron wood and cedar.

Question 10.
Write any five Biosphere Reserves in India.
Answer:

1. Biosphere Reserves are the protected areas of land coastal environments where in people are an integral component of the system.
2. The Indian Government has established 18 Biosphere Reserves. Gulf of Mannar Nilgiris, Agasthiamalai, Kanjanjunga, Great Nicobar etc.

Question 11.
What is ‘Project Tiger’?
Answer:
Project Tiger was launched in April 1973 with the aim to conserve tiger population in specifically constituted “Tiger Reserves” in India. This project is benefited tremendously, with an increase of over 60% – the 1979 consensus put the population at 3,015.

VI. Distinguish between

Question 1.
Weather and Climate.
Answer:
Weather:

1. State of the atmosphere of a place at a given point of time.
2. Weather changes occur daily.
3. Temperature, wind pressure, humidity duration of sunlight and rainfall decides the weather.

Climate:

1. Accumulation of daily and seasonal weather events of a given location over a period of time.
2. It is an average of weather condition over a period of 30-35 years.
3. Climate of a place is determined by Latitude, altitude, distance from the seas, relief features etc.

Question 2.
Tropical Evergreen Forest and Deciduous Forest.
Answer:
Tropical Evergreen forest:

1. These forests are found in the areas where the annual rainfall is 200 cm and more.
2. The tress of these forests do not shed their leaves.
3. Rubber, iron wood, Mahogony are some of the main trees.

Deciduous Forest:

1. These forests are found in the areas with 100 to 200cm annual rainfall.
2. The trees of these forests shed their leaves in spring and early summer.
3. Sandalwood, teak, sal, padak are some of the main trees.

Question 3.
North East Monsoon and South West Monsoon.
Answer:
North East Monsoon:

1. These monsoon winds blow from North-east to South west.
2. They blow during the month of October-November.
3. TamilNadu and Andhra Pradesh gets rainfall from this monsoon.

South West Monsoon:

1. These monsoon winds blow from South west towards North east.
2. They blow during the month of June-September.
3. 75% of India’s rainfall is from this monsoon winds.

VII. Give reasons for the following topics

Question 1.
Western Coastal plain is narrow.
Answer:
It lies between the Western Ghats and Arabian Sea.
It is a narrow plain, which stretches from Gujarat to Kerala with an average width of 50 – 80 km. It is mainly characterised by sandy beaches, coastal sand, dunes, mud flats, lagoons, estuary, laterite platforms and residual hills.

Question 2.
India has a tropical monsoon climate.
Answer:
Latitudinally India lies between 8°4′ N and 37°6’N latitudes. Tropic of Cancer (23° 30’N) divides the country into two equal halves . Most parts of the country’ lie in the Tropical Zone and receives rainfall from monsoon winds which is the dominating climatic factor. Hence India has Tropical monsoon climate.

Question 3.
Mountains are cooler than the plains.
Answer:
When the altitude increases, the temperature decreases. Temperature decreases at the rate of 6.5°C for every 1000 metres of ascent. Hence, places in the mountains are cooler than the places on the plains. That is why the places located at higher altitudes even in South India have cool climate. Ooty and several other hill stations of South India and of the Himalayan ranges like Mussoorie, Shimla, etc., are much cooler than the places located on the Great Plains.

VIII. Write in detail

Question 1.
Write about South West Monsoon.
Answer:

1. Southwest monsoon season is also known as the rainy season in India.
2. The onset of Southwest monsoon season takes place over the southern tip of the country’ by the first week of June, advances along the Konkon coast in early June and covers the whole country by 15th July.
3. Jet stream and ELNino are the two factors that determine the occurrence of Southwest monsoon.
4. Due to the high temperature over north India creates a low-pressure trough which draws the moisture-laden winds from the Indian Ocean towards the Indian landmass.
5. The sudden approach of monsoon wind over south India with ‘ lightning and the thunder indicates the onset of south-west monsoon.
   This is also known as “break or burst of monsoon”.
6. The monsoon winds strike against the southern tip of the Indian landmass and get divided into two branches.
   • (a) Arabian sea branch (of Southwest monsoon)
   • (b) The Bay of Bengal branch (of Southwest monsoon)

(a) Arabian sea branch of South west monsoon:

• The Arabian sea branch of south west monsoon gives heavy rainfall to the west coast of India as it is located in the wind wards side of the Western Ghats.
• The other part which advances towards north strikes against the Himalayan mountains results in heavy rainfall in north.

As Aravalli mountains lie parallel to the wind direction. Rajasthan and the western parts do not get much rainfall.

(b) Bay of Bengal branch of south west monsoon:

• The Wind from Bay of Bengal moves towards north east India and Myanmar.
• This wind is trapped by Garo, Khasi and Jaintia hills and gives the heaviest rainfall to Meghalaya (at Mawsynram).
• This wind gets deflected towards west.
• When the wind moves from east to west rainfall decreases as it looses its moisture.
• Tamil Nadu receives only a meager rainfall as the state is located on the leeward side.

About 75% of India’s rainfall is from the south west monsoon.

Question 2.
Describe the forests of India.
Answer:
Natural Vegetation refers to a plant community which has grown naturally without human aid
and has been left undisturbed by human for a long time.

Tropical Evergreen Forest:
These forests are found in areas with 200 cm or more annual rainfall.The annual temperature is about more than 22°C and the average annual humidity exceeds 70 percent in this region. Western Ghats in Maharashtra, Karnataka, Kerala, Andaman-Nicobar Islands, Assam, West Bengal, Nagaland, Tripura, Mizoram, Manipur and Meghalaya states have this type of forests. The most important trees are rubber, mahogany, ebony, rosewood, coconut, bamboo, cinchona, candes, palm, iron wood and cedar.

Tropical Deciduous Forest:
It covers a large area of the Peninsula and northern India, where the rainfall is from 100 to 200 m. These trees of the forests shed their leaves for a few weeks in early summer. The main trees are teak, Sandalwood, deodars, sisam, sal and redwood.

Tropical Dry Forest:
These are found in the areas with 50 to 100 cm. annual rainfall.They represent a transitional type of forests. These are found in east Rajasthan, Haryana, Punjab, Western Uttar Pradesh, Madhya Pradesh, Eastern Maharashtra, Telangana, West Karnataka and East Tamilnadu. The important species are mahua, banyan, amaltas, palas, haldu, kikar, bamboo, babool, khair etc.,

Mountain or Montane Forest:
These forests are classified on the basis of altitude and amount of rainfall. Accordingly two different types of forests namely Eastern Himalayas Forests and Western Himalayas Forests. Eastern Himalayan Forest: These are found on the slopes of the mountains in north-east states. They receive rainfall of more than 200 cm. The vegetation is of evergreen type. Sal, oak, laurel, amura, chestnut, cinnamon are the main trees from 1200 to 2400 m altitude oak, birch, silver, fir, fine, spruce and juniper are the major trees from 2400 to 3600 m height. Western Himalayan Forest: The rainfall of this region is moderate. They are found n the states of Jammu and Kashmir, Himachal Pradesh and Uttarakhand. In altitude from 900 to 1800 m, chir tree is the most common tree. The other important trees of this region are sal, semal, dhak, jamun and jujube.

Alpine Forest:
It occurs all along the Himalayas with above 2400 m altitude. These are purely having coniferous trees. Oak, silver fir, pine and juniper are the main trees of these forests. The eastern parts of Himalayas has large extent of these forests.

Tidel Forest:
These forests occur in and around the deltas, estuaries and creeks prone to tidal influences and as such are also known as delta or swamp forests. The delta of the Ganga-Brahmaputra has the largest tidal forest. The deltas of Mahanadi, Godavari and Krishna rivers are also known for tidal forests. These are also known as mangrove forest.

Coastal Forest:
These are littoral forests. Generally, coastal areas have these types of forests. Casurina, palm and coconut are the dominant trees. Both the eastern and western coasts have this type of forests.

Riverine Forest:
These forests are found along the rivers on Khadar areas. These are known for tamarisk and tamarind trees. The rivers of Great Plains are more prominent for this type of natural vegetation.

Question 3.
Write the names of biosphere reserves and their location in India.
Answer:
The Indian Government has established 18 Biosphere Reserves which protect larger areas of natural habitat and often include one or more national parks along with the buffer zones that are open to some economic uses.

Biosphere Reserves	State
Achanakmar-Amarkantak	Madhya Pradesh, Chhattisgarh
Agasthyamalai	Kerala
Dibru Saikhowa	Assam
Dihang Dibang	Arunachal Pradesh
Great Nicobar	Andaman and Nicobar Islands
Gulf of Mannar	Tamil Nadu
Kachch	Gujarat
Kanchenjunga	Sikkim
Manas	Assam
Nanda Devi	Uttarakhand
The Nilgiris	Tamil Nadu
Nokrek	Meghalaya
Pachmarhi	Madhya Pradesh
Simlipal	Odisha
Sundarbans	West Bengal
Cold desert	Himachal Pradesh
Sesahachalam hills	Andhra Pradesh
Panna	Madhya Pradesh

IX. Map

Mark the following on the outline map of India.

Question 1.
Direction of South West Monsoon wind.
Answer:

Question 2.
Direction of North East Monsoon wind.
Answer:

Question 3.
Areas of heavy rainfall.
Answer:

Question 4.
Mountain forests.
Answer:

Question 5.
Panna biosphere reserve
Answer:

Question 6.
Agasthiyamalai biosphere reserve
Answer:

TB. PNo: 99
Find Out

Question 1.
Find out the temperature of Ooty (2240m). If it is 35°C in Chennai (6.7 m).
Answer:
For every 1000 mt altitude temperature decreases by 6.5°C . So the temperature of Ooty is nearly 15°C.

TB. PNo: 102
HOTS

Question 1.
Why is Mawsynram, the wettest place in the world?
Answer:
Mawsynram in Meghalaya receives the highest rainfall (1141 cm) in the world. Almost daily it rains. Thus make this place a swampy and the wettest due to very dense vegetation.

Samacheer Kalvi 10th Social Science Climate and Natural Vegetation of India Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The most dominant factor which affects the climate of India is:
(a) Relief
(b) Monsoon winds
(c) Temperature
(d) Soil
Answer:
(b) Monsoon winds

Question 2.
The Local storms in the north eastern part of India during the weather seasons are called
(a) Loo
(b) Norwesters
(c) Mangoshowers
Answer:
(a) Loo

Question 3.
Seventy-five percentage of Indian rainfall is from this wind:
(a) Western Disturbance
(b) North East monsoon
(c) Norwesters
(d) South West monsoon
Answer:
(d) South West monsoon

Question 4.
The mountain which stands parallel to the direction of the south-west monsoon wind ….
(a) Vindhya
(b) Aravalli
(c) Satpura
Answer:
(b) Aravalli

Question 5.
The ……………. forests are found in the region where the rainfall is 200 cm and above.
(a) Tropical evergreen
(b) Tidal
(c) Tropical deciduous
(d) Alpine
Answer:
(a) Tropical evergreen

Question 6.
……… experience continental climate.
(a) Chennai
(b) Mumbai
(c) Delhi
Answer:
(c) Delhi

Question 7.
The term ……………. includes animals of any habitat in nature.
(a) Mammals
(b) Forests
(c) Insects
(d) Wild life
Answer:
(d) Wild life

Question 8.
In India, 85% of the rain is received from the ……….
(a) North-east
(b) South-west
(c) South-east
Answer:
(b) South-west

Question 9.
In the year ……………. United nations Convention on Biological Diversity (CBD) recognizes the sovereign rights of the states to use their own Biological Resources.
(a) 1992
(b) 1982
(c) 1979
(d) 1929
Answer:
(a) 1992

Question 10.
The ……… prevents the cold polar winds blowing from Central Asia.
(a) Aravalli Hills
(b) Bay of Bengal
(c) Himalayas
Answer:
(c) Himalayas

Question 11.
The highest rainfall region in India is located in this state:
(a) Assam
(b) Bihar
(c) Meghalaya
(d) Manipur
Answer:
(c) Meghalaya

Question 12.
There is a peculiar uniformity in the climate of India due to its unique ……..
(a) Geography
(b) Physiography
(c) Demography
Answer:
(b) Physiography

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (iii)
B. (i)
C. (v)
D. (ii)
E. (iv)

Question 2.
Match the Column I with Column II.

Answer:
A. (vi)
B. (iii)
C. (v)
D. (ii)
E. (iv)
F. (i)

Question 3.
Match the Column I with Column II.

Answer:
A. (v)
B. (i)
C. (ii)
D. (vi)
E. (iv)
F. (iii)

III. Consider the given statements and choose the correct option from the given below ones

Question 1.
Assertion(A): Peninsular India enjoys equable climate.
Reason(R): The peninsular region is surrounded by the seas on three sides, not very far from the sea.
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 2.
Assertion(A): Two different types-of mountain forests are in India namely Eastern Himalayan forests and Western Himalayan forests.
Reason(R): Mountain forests are classified on the basis of altitude and amount of Rainfall.
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(b) Both (A) and (R) are true: R does not explain A

Question 3.
Assertion(A): Systematic change in the direction of planetary winds is known as monsoons.
Reason(R): Monsoon winds originates due to the seasonal migration of planetary winds and pressure belts following the position of the Sun.
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(c) (A) is correct (R) is false

Question 4.
Assertion(A): Rajasthan remains as desert.
Reason(R): As Aravalli mountain is located parallel to the Arabian Sea branch South west Monsoon winds the western part (Rajasthan) do not receive much rainfall. To the Bay of Bengal Branch of South west Monsoon wind it is located on the leeward side.
(a) Both (A) and (R) are true: R explains A
(b) Both (A) and (R) are true: R does not explain A
(c) (A) is correct (R) is false
(d) (A) is false (R) is true
Answer:
(a) Both (A) and (R) are true: R explains A

IV. Choose the inappropriate answer

Question 1.
The pre-monsoon showers are known as mango showers in:
(a) Kerala and Karnataka
(b) Punjab and Haryana
(c) Hot weather season
(d) Helps quick ripening of mangoes
Answer:
(b) Punjab and Haryana

Question 2.
Tropical deciduous forests trees are of economic importance:
(a) Have valuable trees like teak, sal.
(b) To make fragnant oil, varnish, perfumes.
(c) Do not shed their leaves.
(d) Found in rainfall areas of 100 to 200 cm.
Answer:
(c) Do not shed their leaves.

Question 3.
Tidal forests are also known as swamp or delta forests.
(a) These forests are not prone to tidal waves.
(b) Known as mangrove forests.
(c) Occur in and around deltas, estuaries.
(d) Prone to tidal influences.
Answer:
(a) These forests are not prone to tidal waves.

Question 4.
Biosphere Reserves are protected areas of coastal and land environment.
(a) Indian Government has established 18 Biosphere Reserves.
(b) Do not protect areas of natural habitat.
(c) People are an integral component of the system.
(d) One or more National parks preserves along with buffer zone.
Answer:
(b) Do not protect areas of natural habitat.

V. Answer briefly

Question 1.
Name the classification of Natural vegetation.
Answer:
Natural Vegetation can be classified as:

1. Tropical Evergreen forests
2. Tropical deciduous forests
3. Tropical dry forests
4. Desert and semi-desert
5. Mountain forests
6. Alpine forests and
7. Tidal forests

Question 2.
Name the factors affecting the climate of India.
Answer:
Climate of India is affected by the factors of latitude, distance from the seas, Monsoon wind, relief features and jet stream.

Question 3.
The climate and weather conditions in India are governed by the three-atmosphere conditions. Name them.
Answer:

1. The Pressure and Surface winds.
2. Upper air Circulation
3. Western cyclonic disturbances and tropical conditions

Question 4.
What is ElNino? How does it affect the climate of India?
Answer:
ElNino is a complex global phenomena of weather that appears once eveiy five to ten years. It is a cause for the delay of onset of the southwest monsoon in India.

Question 5.
What is the Characteristic features of monsoon rains in India?
Answer:

1. The Monsoon rains are pulsating in nature
2. They can cause heavy rainfall in one part and drought in the other.
3. They are known for their uncertainties.

Question 6.
What is the role of Jet stream regarding the climate of India?
Answer:

1. The arrival and departure of monsoon winds is determined by Jet stream.
2. Cause tropical depressions both during South west monsoon and North east monsoon.
3. Plays a vital role in bringing western disturbances to India there by helping winter wheat cultivation.

Question 7.
What values are associated with the monsoon in India?
Answer:

• Monsoon acts as unifying bond for India.
• The unifying influence of the monsoon on the Indian Subcontinent is quite perceptible.
• The Seasonal alteration of the wind systems and the associated weather conditions provide a rhythmic cycle of seasons.
• The Indian landscape, its animal and plant life, its entire agricultural calender and the life of the people, including their festivities, revolve around this phenomenon.
• Year after year, people of India from North to South and from east to west, eagerly await the arrival of the monsoon. These monsoon winds binds the whole country by providing water to set the agricultural activities in motion.
• The rivers valleys which carry this water also unite as a single river valley unit.

Question 8.
Give a brief note on the Indian Board for Wild life:
Answer:

1. The Indian Board for wild life was constituted in 1952 to suggest means of protection, conservation and management of wild life to the Government of India.
2. The Government of India enacted wild life (protection) Act in 1972 with the objective of effectively protecting the wild life.

Question 9.
Explain the steps taken to conserve wildlife.
Answer:
The Wild Life Act Of India protects and conserves this grest heritage of nation. The first weak of October is observed as Wild life Week Of India.

Question 10.
Give the Full form of these abbreviations.

1. IBWL
2. CBD
3. ITCZ

Answer:

1. IBWL : Indian Board for Wild Life.
2. CBD: Convention on Biological Diversity.
3. ITCZ : Inter Tropical Convergence Zone.

Question 11.
Why does the coromandal coast face frequent cyclones?
Answer:
The north east monsoon winds by crossing the Bay of Bengal absorbs moisture and gives heavy rain to the coromandal coast. These are frequent cyclones formed in the Bay of Bengal and they cause heavy damage to life and property along the coromandal coast.

Question 12.
Give a brief description of the Mangrove forests.
Answer:

• The mangrove tidal forests are found in the areas of coasts influenced by tides. Hence, mangroves are the common varities with roots of the plants submerged under water. The deltas of the Ganga, the Mahanadi, the Krishna, the Godavari and the Kaveri are covered by such vegetation. In the Ganga-Brahmaputra delta sundari trees are found which provides durable hard timber.
• Palm, coconut, Keora agar also grow in some parts of the delta.
• Royal Bengal Tiger is the famous animal in these forests. Turtles, crocodiles, gharials and snakes are also found in these forests.

VI. Distinguish between

Question 1.
Winter/Cold weather and Summer/Hot weather season.
Solution:
Winter or Cold weather season:

1. In India,winter weather period is January-February.
2. The mean temperature increases from North to South.
3. Western Disturbances occurs in this season.
4. Generally fine weather and low tempertaure.

Summer or Hot weather season:

1. The summer season is from March- May.
2. The mean tempertaure increases from South to North.
3. Mango showers, Norwesters or Kalbaisakhi occurs in this season.
4. Generally hot and dry weather.

Question 2.
Heavy rainfall and less/low rainfall region.
Answer:
Heavy rainfall region:

1. These areas get annual rainfall of 200 cms and above.
2. Western coast, Assam, South Meghalaya are heavy rainfall areas.

Less or low rainfall region:

1. These areas get annual rainfall less than 100 cms.
2. Rajasthan, Punjab, Haryana, Western and South western parts of Uttar Pradesh, plateau region gets less rainfall.

Question 3.
Windward side and Leeward side.
Answer:
Windward side:

1. The slope of the mountain that lie on the path of rain bearing winds.
2. The windward side gets more rainfall.
3. Western slopes of Western Ghats – West coastal plains.

Leeward side:

1. The slope of the mountain that do not face the rain bearing winds.
2. The Leeward side gets less or no rainfall.
3. Eastern slopes of Western Ghats – Deccan Plateau.

Question 4.
Eastern and Western Himalayan forests.
Answer:
Eastern Himalayan forests:

1. The vegetation of this forest is’ evergreen as these forests receive more than 200cm rainfall.
2. Pine, Sal Fir, Oak, Laurel are some of the main trees of these forests.
3. These forests are found in the North Eastern states.

Western Himlayan forests:

1. The rainfall of this region is moderate and have varied vegetation regards to altitude.
2. Upto 900m altitude semi desert vegetation from 900m – 1800m chir tree and sal, at 1800m conifer trees.
3. These forests are found in the states of Jammu and Kashmir, Himachal Pradesh and UttaraKhand.

VII. Give reasons for the following topics

Question 1.
Kolkatta receives more rainfall than Bikaner in Rajasthan.
Answer:
Air near the coast has more moisture and greater potential to produce precipitation. Due to this fact Kolkatta near the coast receives more rainfall (119cm) than Bikaner (24cm) which is located in the interior part.

Question 2.
In India Conservation and management of Biodiversity is necessary why?
Answer:
Hunting, Poaching, deforestation and encroachments in the natural habitats have caused extinction of some species and many are in the danger of extinction. The role of wild life in maintaining the ecological balance made it necessary for conservation and management of Biodiversity.

Question 3.
Relief of India has a great bearing on climate.
Answer:
The elements of climate such as temperature, atmospheric pressure, direction of winds and the amount of rainfall are affected by the presence of relief features as they act as a climatic barrier like the Himalayas and Western Ghats.

VIII. Write in detail

Question 1.
What are the major determinants of climate of a place? Explain them.
Answer:
The major determinants of climate of a place are,

1. Latitude
2. Altitude
3. Distance from the seas
4. Monsoon winds
5. Relief features (Mountains)
6. Jet Streams

1. Latitude:
Latitudinally, India lies between 8°4’N and 37°6’N latitudes. The Tropic of cancer divides the country into two equal halves. The area located to the south of Tropic of cancer experiences high temperature and no severe cold season throughout the year whereas, the areas to the north of this parallel enjoys subtropical climate. Here, summer temperature may rise above 40°C and it is close to freezing point during winter.

2. Altitude:
As one goes from the surface of the earth to higher altitudes, the atmosphere becomes less dense and temperature decreases. The hills are therefore cooler during summer.

3. Distance from the seas:
Distance from the sea does not cause only temperature and pressure variations but also affects the amount of rainfall. As the distance from the sea increased its moderating influence decreases and the people experience extreme weather conditions. This condition is known as continentality.(i.e.) Very hot during summers and very cold during winter.

4. Monsoon winds:
The most dominant factor which affects the climate of India is the monsoon winds. These are seasonal reversal winds and India remains in the influence of these winds for a considerable part of a year. Though, the sun’s rays are vertical over the central part of India during the mid-June, the summer season ends in India by the end of May. It is because the onset of southwest monsoon brings down the temperature of the entire India and causes moderate to heavy rainfall in many parts of the country. Similarly, the climate of southeast India is also influenced by northeast monsoon.

5. Relief features (Mountains):
Relief of India has a great bearing on major elements of climate such as temperature, atmospheric pressure, direction of winds and the amount of rainfall. High mountains act as barriers for cold or hot winds; they may also cause precipitation if they are high enough and lie in the path of rain-bearing winds. The leeward side of mountains remains dry.

6. Jet Streams:
Jet streams are the fast moving winds blowing in a narrow zone in the upper atmosphere. According to the Jet stream theory, the onset of southwest monsoon is driven by the shift of the sub tropical westerly jet from the plains of India towards the Tibetan plateau. The easterly jet streams cause tropical depressions both during southwest monsoon and retreating monsoon.

Question 2.
Write about the factors that affect the climate of India.
Answer:
Climate of India is affected by the factors of latitude, altitude, distance from the seas, monsoon winds and jet streams.

Latitude:

1. Latitudinally India is located in the Tropical belt between 8°4’N and 37°6’N latitudes.
2. The tropic of cancer divides the country into two equal halves.
3. This enables the places south of Tropic of cancer (23°30’N) to experience high temperature and no severe cold.
4. The places north of Tropic of cancer enjoy sub tropical climate.

Altitude:

1. When the altitude increases, temperature decreases as per the phenomena. “Normal Lapse rate”. For every 1000 mts of ascent the temperature decreases at the rate of 6.5°C.
2. Hence the places in the mountains are cooler than the places on the plains.
3. Even in South India places at higher altitude have cool climate.

Distance from the sea:

1. Distance from the sea not only causes temperature and pressure variations but also affects the amount of rainfall.
2. The entire area of peninsular region as it is surrounded by seas on three sides having the temperature equable throughout the year.
3. Areas of central and north India experiences much seasonal variation in temperature due to the absence of seas.

Monsoon winds:

1. The most dominant factor which affects the climate of India is the. monsoon winds.
2. India is influenced by the South west monsoon and North east monsoon from June to September and October, November respectively.
3. Indian agriculture is at the mercy of monsoons.
4. India experiences Tropical monsoon climate.

Relief:

1. Relief of India has a great bearing on major elements of climate such as temperature, atmospheric pressure direction of wind and amount of rainfall.
2. The mighty Himalayas in the north act as a climatic barrier preventing the freezing cold winds from central Asia away from India.
3. The Western ghats act as the barrier for south west monsoon winds causing rainfall to the western slopes, and the eastern slopes remain as rain shadow region.

Jet Stream:

1. Jet streams are the fast moving winds blowing in the narrow zone of upper layers of atmosphere.
2. These air currents play a dominant role in bringing the onset of South west monsoon and withdrawal of monsoon winds.
3. More over they are the main reason in bringing the Western Disturbances to the North Western part of Punjab and Haryana causing rainfall and enable the cultivation of winter wheat.
4. It causes snow fall in Jammu and Kashmir region.

Thus the Tropical monsoon = climate of India revolve around these factors

IX. Map Work

Mark the following on the outline map of India.

Question 1.
Areas of low rainfall
Answer:

Question 2.
Any 4 Biosphere Reserve
Answer:

Question 3.
Any 5 National parks
Answer:

Question 4.
Any 3 Wild animal sanctuary
Answer:

Question 5.
Any 2 Bird Sanctuary
Answer:

Question 6.
Top 5 states having maximum forest cover
Answer:

Question 7.
Top 5 states where forest cover is decreased
Answer:

Students can download 10th Social Science Geography Chapter 1 India: Location, Relief and Drainage Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 1 India: Location, Relief and Drainage

Samacheer Kalvi 10th Social Science India: Location, Relief and Drainage Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
The north-south extent of India is:
(a) 2,500km
(b) 292,933 km
(c) 3,214km
(d) 2,814km
Answer:
(c) 3,214km

Question 2.
The Southern most point of India is ……….
(a) Andaman
(b) Kanyakumari
(c) Indira Point
(d) kavaratti
Answer:
(c) Indira Point

Question 3.
The extent of Himalayas in the east-west is about:
(a) 2,500 km
(b) 2,400 km
(c) 800 km
(d) 2,200 km
Answer:
(a) 2,500 km

Question 4.
……… River is known as ‘Sorrow of Bihar’.
(a) Narmada
(b) Godavari
(c) Kosi
(d) Damodar
Answer:
(c) Kosi

Question 5.
Deccan Plateau covers an area of about sq.km.
(a) 8 lakh
(b) 6 lakh
(c) 5 lakh
(d) 7 lakh
Answer:
(d) 7 lakh

Question 6.
A landmass bounded by sea on three sides is referred to as ………
(a) Coast
(b) Island
(c) Peninsula
(d) Strait
Answer:
(c) Peninsula

Question 7.
The Palk Strait and Gulf of Mannar separates India from:
(a) Goa
(b) West Bengal
(c) Sri Lanka
(d) Maldives
Answer:
(c) Sri Lanka

Question 8.
The highest peak in South India is …………
(a) Ooty
(b) Kodaikanal
(c) Anaimudi
(d) Jindhagada
Answer:
(c) Anaimudi

Question 9.
Plains are formed by the older alluviums.
(a) Bhabar
(b) Tarai
(c) Bhangar
(d) Khadar
Answer:
(c) Bhangar

Question 10.
Pulicat Lake is located between the states of ………….
(a) West Bengal and Odisha
(b) Karnataka and Kerala
(c) Odisha and Andhra Pradesh
(d) Tamil Nadu and Andhra Pradesh
Answer:
(d) Tamil Nadu and Andhra Pradesh

II. Match the following

Answer:
A. (iii)
B. (i)
C. (v)
D. (ii)
E. (iv)

III. Give Reasons

Question 1.
The Himalayas are called young fold mountains.
Answer:
The Himalayas are called young fold mountains. Because they have been formed only few million years ago and also they were formed because of the folding of the Earth crust due to tectonic activity’.
[OR]
High pointed peaks and parallel ranges is the features of young fold mountains. Since the Himalayas have these features they are called young fold mountains.

Question 2.
North Indian Rivers are perennial.
Answer:
Most of the North Indian Rivers are perennial. It means that they have water throughout the year. These rivers receive water from rain as well as from melted snow from the lofty mountains.

Question 3.
Chottanagpur Plateau is rich in mineral resources.
Answer:
This region is a part of the ancient Gondwana region. So, Chotanagpur plateau is rich in mineral resources like iron ore and coal.

Question 4.
The great ludian desert ii called Marusthall.
Answer:
The Thar desert, also known as the Great Indian desert is a large arid region in the north
western part of the Indian Subcontinent that covers an area of 2,00,000 Km² and forms a natural boundary between India and Pakistan.
Marusthali means sand-dune. It covered eastern portion of the Great indian Thar Desert in western Rajasthan. It extends over about 24,000 square miles north of the Luni River.

Question 5.
The Eastern states are called seven sisters.
Answer:
The Eastern states in India are the continuous seven states. Assam, Arunachal Pradesh, Nagaland, Mizoram, Manipur, Tripura and Meghalaya. “A paradise unexplored” named by a journalist Jyothi Prakash Salkia in 1972 during the inaugural foundation of North East states.

Question 6.
The river Godavari is often referred to as Vridha Ganga.
Answer:

1. The Godavari is India’s second longest river after Ganga.
2. It rises from the slopes of the Western Ghats in the Nasik district of Maharashtra.
3. It covers a large number of states as the Ganga does. Because of its large size and extend among the peninsular rivers, the river Godavari is often referred to as Vridha Ganga.

IV. Distinguish between the following

Question 1.
Himalayan rivers and Peninsular rivers.
Answer:
Himalayan Rivers:

1. Originate from the Himalayas.
2. Perennial in nature.
3. Long and Wide.
4. Middle and Lower courses are navigable.
5. Unsuitable for hydropower generation.

Peninsular Rivers:

1. Originate from Western ghats.
2. Non-perennial in nature.
3. Short and narrow.
4. Not useful for navigation.
5. Suitable for hydro-power generation.

Question 2.
Western Ghats and Eastern Ghats.
Answer:
Western ghats:

1. Western ghats forms the Western edge of the peninsular plateau.
2. It runs parallel to the Arabian sea coast.
3. They are continuous range.
4. Anaimudi is the highest peak.

Eastern ghats:

1. Eastern ghats form the Eastern edge of the peninsular plateau.
2. It runs parallel to the Bay of Bengal coast.
3. They are not continuous dissected by east flowing rivers.
4. Mahendragiri is the highest peak.

Question 3.
Himadri and Himachal.
Answer:
Himadri:

1. Northern most range of the Himalayas.
2. Known as the Greater Himalayas.
3. Lofty peaks like Mt.Everest, Kanchenjunga etc., are located in this range.
4. Region of permanent snow cover.

Himachal:

1. Middle range of the Himalayas.
2. Known as the lesser Himalayas.
3. Major hill stations like Shimla, Daijeeling etc., are located in this region.
4. Subjected to extensive erosion.

Question 4.
Western Coastal Plains and Eastern Coastal Plains.
Answer:
Western Coastal plains:

1. Lies between Western ghats and Arabian Sea.
2. It extends from Rann of Kutch in the North to Kanyakumari in the South.
3. Dotted with sandy beaches, lagoons and estuary.
4. It is known as Konkan plains in the North Kanara in the middle and Malabar in the South.

Eastern Coastal plains:

1. Lies between Eastern ghats and the Bay of Bengal.
2. It stretches along the states of West Bengal, Odisha, Andhra Pradesh and Tamil Nadu.
3. Has regular shoreline and composed of alluvial deposits.
4. Northern part (Mahanadhi-Krishna) called as Northern circars and Southern part (Krishna-Kaveri) is called Coromandal coast.

V. Answer in brief

Question 1.
Name the neighbouring countries of India.
Answer:
The neighbouring countries of India are Pakistan in the West, Afghanistan in the North-West, China, Nepal and Bhutan in the North and Bangladesh and Myanmar in the East and Srilanka in the South.

Question 2.
Give the importance of IST.
Answer:
To avoid the confusion of time in different states of India. One meridian is taken to have a uniform time for a whole country. Therefore 80° 30′ E has been chosen as the Standard Meridian of India which is almost passing from the centre of India.

Question 3.
Write a short note on Deccan Plateau.
Answer:

1. Deccan plateau is the largest part of the peninsular plateau.
2. It is roughly triangular in shape.
3. It covers an area of 7 lakh sq km.
4. The height ranges from 500 to 1000m above sea level.
5. It extends from Rajmahal hills on the East to Kanyakumari in the South. Satpura range in the West to Kanyakumari in the South. Bordered by Western Ghats on the West and Eastern ghats on the East.

Question 4.
State the west-flowing rivers of India.
Answer:

• The Narmada and the Tapi are the west flowing rivers of the Peninsular India.
• These rivers drain into the Arabian Sea.
• These rivers form estuaries on the west coast.
• These rivers are devoid of an large tributary system.
• Narmada river is the largest among the west flowing rivers of peninsular India. Its principal tributaries are Bushner, Halon, Heran, Banjar, Dudhi, Shakkar, Tawa, Bama and Kolar.
• Tapti river is one of only the three rivers in peninsular India that run from east to west. The others being the Narmada and the Mahi.
• The major tributaries are Vaki, Gomai, Arunavati, Aner, Nesu, Buray Panjhra and Bori. It outfall into the Arabian sea through the Gulf of Cambay.

Question 5.
Write a brief note on the island group of Lakshadweep.
Answer:

1. The Lakshadweep islands of India are located off the West coast of India.
2. These islands are of coral origin.
3. It covers an area of 32 sq km and consists of 27 islands.
4. Kavaratti is the administrative capital of Lakshadweep.
5. Earlier it had three divisions namely Laccadives, Minicoy and Aminidivi and was named as Lakshadweep in 1973.
6. “Pitt Island” of this group has a bird sanctuary and it is uninhabited.

VI. Answer In a paragraph

Question 1.
Explain the divisions of the Northern Mountains and its importance to India.
Answer:

• The Himalayas geologically young and structurally fold mountains stretch over the northern borders of India.
• The Himalayas represent the loftiest and one of the most rugged mountain barriers of the world.
• The mountain ranges run in a west-east direction from India to the Brahmaputra.

Question 2.
Give an account on the major peninsular rivers of India.
Answer:

1. The rivers in South India are called the Peninsular rivers.
2. Most of these rivers originate from the Western ghats.
3. These rivers are seasonal and are mainly fed by rain.
4. Based on the direction of flow the Peninsular rivers are divided into East flowing rivers and West flowing rivers.

East flowing rivers:

1. Mahanadi: Originates near Sihawa in Raipur district of Chattisgarh.
   • Flows through Odisha, Jharkand, Chattisgarh (851 km in length)
   • Major tributaries: Seonath, Telen, Sandur and lb.
   • Distributaries: Paika, Birupa, Chitartala, Genguti and Nun.
   • These distributaries forms the Delta of Mahanadhi, one of the largest delta in India.
   • This river flows into Bay of Bengal.

(ii) Godavari:

• It is the longest river (1,465km) among the peninsular rivers covers 3.13 lakh km2 area.
• Originates in Nasik district of Maharashtra.
• Flows through the States of Telangana and Andhra Pradesh ends into Bay of Bengal.
• Major distributaries: Puma, Penganga, Pranitha, Indravathi, Tal and Salami.
• Distributaries: Near Rajahmundry divides into two channels. Vasishta and Gautami and form one of the largest delta.
• Fresh water lake: Kolleru is located in the deltaic region of Godavari.

(iii) Krishna:

• It is the second longest peninsular river (1400 km) covers 2.58 lakh sq km area.
• Originates from a spring in Mahabaleshwar in the Western ghats of Maharashtra.
• Flows through Andhra Pradesh.
• Major tributaries: Bhima, Peddavagu, Musi, Koyna and Thungabhadra.
• Joins in Bay of Bengal at Hamasaladevi.

(iv) Kaveri:

• Originates at Talakaveri – Kudagu hills of Karnataka (800km).
• It is also known as Dakshin Ganga or Ganga of the South.
• Main Tributaries: Hemavathi, Kabini, Bhavani, Arkavathy, Amaravathi, Harangi etc.
• Distributary – Coleroon
• Sacred lslands made by river Kaveri: Sri ranagpattinam(Kamataka) Srirangam (TamilNadu) Waterfalls – Sivasamudram.
• Flows through Karnataka and TamilNadu.
• Enters TamilNadu through Hoghenekkal Falls (Dharmapuri).
• Drains into Bay of Bengal at Poompuhar.

West Flowing Rivers:

(i) Narmadha:

• Origin: Araarkantak Plateau (Madhya Pradesh)
• Length: 1312 km covers an area of 98,796 sq km.
• Largest among the West flowing rivers.
• Tributaries: Burhner, Halon, Heran, Banjar, Dudhi, Shakkar, Tawa, Bama, Kolar.
• States benefited: Madhya Pradesh, Maharashtra.
• Ends into Arabian Sea through the Gulf of Cambay.
• Forms 27 km long estuary.

(ii) Tapti:

• Rises near Multani in the Betul district of Madhya Pradesh.
• Length: 724 km. Covers an area of 65,145 sq km.
• Tributaries: Vaki, Gomai, Arunnavati, Aner, Nesu, Buray, Panjhra and Bori.
• Outfalls into the Arabian Sea through Gulf of Cambay.
• States: Flows through Madhya Pradesh and Maharashtra.
• Since all these rivers flow in the plateau region they are swift and are useful for hydro power generation.

Question 3.
Give a detailed account on the basin of the Ganga.
Answer:

• On the basis of deposition of Sediments by various rivers and topographical characteristics, the Northern plains of India is divided into the four major regions. Ganga plains is one among them.
• It extends from the Yamuna River in the West to Bangladesh in the East.
• The extensive plain is the largest plain of India covers 3.75 lakh sq. km.
• It is watered by the River Ganga and its tributaries such as Ghaghra, Gandak, Kosi, Yamuna, Chambal, Betwa etc.
• It is formed by the sediments of these rivers and is fertile in nature.
• The general slope of the entire plain is towards East and South-East.
• Ganga plains covers the states of Uttar Pradesh, Bihar and West Bengal.

VII. Map exercises

Mark the following in the outline map of India

Question 1.
Major mountain ranges – Karakoram,Ladakh, Zaskar, Aravaili, Western Ghats,Eastern Ghats.
Answer:

Question2.
Major rivers – Indus, Ganga, Brahmaputra, Narmada, Tapti, Mahanadi, Godavari, Krishna and Kaveri.
Answer:

Question 3.
Major plateaus – Malwa, Chotanagpur, Deccan.
Answer:

VIII. Activities

Question 1.
Observe the Peninsular Plateau map of India and mark the major plateau divisions of India.
Answer:

Question 2.
Prepare a table showing the major West flowing and East flowing rivers of peninsular India.
Answer:
West flowing rivers:

1. Narmada, Tapti, Mahi.
2. Flows into Arabian Sea through Gulf of cambay.
3. Do not make deltas but form estuary.

East flowing rivers:

1. Mahanadhi, Godhavari, Krishna and Kaveri.
2. Flows into Bay of Bengal.
3. Make deltas at their lower courses.

Question 3.
Assume that you are travelling from West Bengal to Gujarat along the beautiful coasts of India. Find out the states which you would pass through?
Answer:
From West Bengal, if we travel along the East coast we could pass through Odisha, Andhra Pradesh, Tamil Nadu states from North to South and from South to North along the West Coast we would pass through the states of Kerala, Karnataka, Goa, Maharashtra and reach Gujarat.

Question 4.
Find out the states through which the river Ganga flows.
Answer:
River Ganga flows through the States of Uttar Pradesh, Bihar and West Bengal.

Question 5.
Prepare a table showing the major rivers in India and findout it’s tributaries, origin, length and area.
Answer:

TB. PNo: 83
Find Out

Question 1.
The number of Union Territories along the western coast and eastern coast.
Answer:
Union Territories along the western coast are:

1. Diu and Daman
2. Dadra and Nagar Haveli
3. Mahe and Lakshadweep.

Union Territories along eastern coast are:

• Pondicherry and Andaman and Nicobar Islands.

Question 2.
Area wise which is the largest and the smallest state?
Answer:

1. Area wise Rajasthan is the largest state (3,42,239 sq.km).
2. The smallest state is Goa (3,702 sq km).

Question 3.
The states which do not have an international border or lie on the largest state.
Answer:
Haryana, Madhya Pradesh, Jharkhand, Chattisgarh.

Question 4.
Classify into four groups each having common frontiers with

1. Pakistan
2. China
3. Myanmar
4. Bangladesh.

Answer:

1. Pakistan – Jammu and Kashmir, Punjab, Rajasthan, Gujarat.
2. China – Jammu and Kashmir, Himachal Pradesh, Uttarkhand, Sikkim, Arunachal Pradesh.
3. Myanmar – Arunachal Pradesh, Nagaland Manipur, Mizoram.
4. Bangladesh – Meghalaya, Assam, West Bengal, Tripura.

TB. PNo: 85
Find Out

Question 5.
Find the Hill stations which are located in the Himalayan Mountains.
Answer:
Major hill stations of the Himalayas are Shimla, Mussoorie, Nainital, Almora, Ranikhet and Darjeeling.

TB. PNo: 95
Find Out

Question 6.
In which river the Gerosappa (jog) fall is found?
Answer:
In the river Sharavathi is the Gerosappa (jog) falls (830m). Second highest waterfalls in India.

Samacheer Kalvi 10th Social Science India: Location, Relief and Drainage Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
India is the ………………… largest country in Asia.
(a) first
(b) second
(c) fourth
(d) third
Answer:
(b) second

Question 2.
Along with Hindukush and Karakoram range ……… provide a natural boundary in the
north.
(a) Aravalli
(b) Satpura
(c) Himalayas
Answer:
(c) Himalayas

Question 3.
The ………………… latitude passes through the middle of the country.
(a) 0°
(b) 23°.30’N
(c) 66°.30’N
(d) 23°.30’S
Answer:
(b) 23°.30’N

Question 4.
The coconut bearing coastal plains are on the ………
(a) east
(b) west
(c) south
Answer:
(c) south

Question 5.
The ………………… is known as the “Roof of the World”.
(a) Armenian knot
(b) Anaimudi
(c) Pamirknot
(d) Mt.Everest
Answer:
(c) Pamirknot

Question 6.
The …….. land gets abundance sunshine from the sun.
(a) mediterranean
(b) tropical
(c) equatorial
Answer:
(b) tropical

Question 7.
The Great Northern plains covers an area of over sq.km.
(a) 5 lakh
(b) 6 lakh
(c) 7 lakh
(d) 8 lakh
Answer:
(c) 7 lakh

Question 8.
The …… divides India into two halves.
(a) tropic of Cancer 231/2° N
(b) equator 0°
(c) tropic of Capricorn 231/2° S
Answer:
(a) tropic of Cancer 231/2° N

Question 9.
The ………………… desert is the world 9th largest sub tropical desert.
(a) Gobi
(b) Atacama
(c) Kalahari
(d) Thar
Answer:
(d) Thar

Question 10.
India is …….. times bigger than Pakistan.
(a) two
(b) five
(c) four
Answer:
(c) four

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (iii)
B. (i)
C. (v)
D. (ii)
E. (iv)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (v)
C. (ii)
D. (iii)
E. (i)

III. Give Reasons

Question 1.
Peninsular Rivers are Non-Perennial.
Answer:
Peninsular rivers originate from the Western Ghats. They have a large seasonal fluctuation in the volume of water as they are solely fed by the rain. So these Rivers are seasonal and non-perennial.

Question 2.
Andaman and Nicobar islands have dense forests.
Answer:
Since these islands lie close to the equator, the climate remains hot and wet throughout the year and has dense forests.

Question 3.
India has close contact with the countries of the West and the East.
Answer:
India’s Southward extension along the Indian ocean and the trans Indian . ocean routes provide a strategic position to India connecting the countries of Europe in the West and the countries of East Asia. Thus, India has close contact with the countries of the West and the East.

Question 4.
India is geographically vibrant and incredible country.
Answer:
The majestic Himalayan peaks in the North, beautiful beaches in the South, the Great Indian desert in the West and the breathtaking natural heritage in the East make India geographically vibrant and an incredible country.

IV. Distinguish between the following

Question 1.
Andaman and Nicobar Islands and Lakshadweep Islands.
Answer:
Andaman and Nicobar Islands:

1. Located in Bay of Bengal.
2. These islands are of volcanic origin.
3. Port Blair is the administrative capital.
4. Consists of nearly 572 islands.

Lakshadweep Islands:

1. Located in Arabian Sea off the West coast of India.
2. These islands are mainly coral origin.
3. Kavaratti is the administrative capital.
4. Consists of nearly 27 islands.

Question 2.
Bhangar plains and Khadar plains.
Answer:
Bhangar plains:

1. Upland alluvial tracts of Great plains.
2. Formed by the older alluvium.
3. Soil is dark, rich in humus.
4. Well drained and fit for agriculture.

Khadar plains:

1. Plains along the courses of the rivers of Great plains.
2. Formed by the newer alluvium.
3. Soil is sandy, silt, clay and mud.
4. Highly fertile.

Question 3.
West flowing rivers and East flowing rivers.
Answer:
West flowing rivers:

1. Flow into Gulf of Cambay.
2. Form estuaries
3. Narmadha, Tapti and Mahi are the major west flowing rivers.

East flowing rivers of Peninsular plateau or South India:

1. Flow into Bay of Bengal.
2. Form Deltas
3. Mahanadhi, Godavari, Krishna and Kaveri are the major east flowing rivers.

Question 4.
Tributary and Distributary.
Answer:
Tributary:

1. A river or stream that joins with the main river.
2. Contributes water to the main river.
3. Eg: Yamuna tributary of river Ganga.

Distributary:

1. A branch or outlet that leaves the main river.
2. Carries water to the sea or lake.
3. Eg: River Coleroon a distributary of river Kaveri.

V. Answer in brief

Question 1.
Mention the tributaries of Godavari.
Answer:
Ghatprabha, Malaprabha, Manjira, Penganga and Neingarga.

Question 2.
Name the boundaries of India.
Answer:
India is bounded by Bay of Bengal on the East, Arabian sea on the West, Indian ocean in the South and the lofty Himalayas in the North

Question 3.
Why do we need a Standard Meridian for India?
Answer:
To avoid time gap of two hours between east and west part of India which may create confusion in working, it is essential to have a Standard Meridian.

Question 4.
How India is politically divided?
Answer:
India is politically divided into 29 states and 7 union territories (Delhi being the National Capital territory) for administrative convenience.

Question 5.
Why is India called a Sub-continent? How it is separated?
Answer:

1. India is called a Sub-continent because it is big landmass, which stands out as a distinct geographical unit from the rest of the continent.
2. It is separated by natural features like mountains and rivers.
3. India is also separated from rest of the continent by the mighty Himalayas.

Question 6.
Name the three major divisions of the Northern Mountains.
Answer:
The three major divisions of the Northern mountains are:

1. The Trans-Himalayas (or) The Western Himalayas
2. The Himalayas
3. Eastern Hills or Purvanchal Hills

Question 7.
Why is Northern Plain most productive part of India?
Answer:
With a rich soil cover combined with an adequate water supply and favourable climate Northern plain is agriculturally a very productive part of India.

Question 8.
How has Northern Plain become a fertile Plain?
Answer:
The plain is formed of alluvial soil. The deposition of alluvium in a large basis lying at the foothills of the Himalayan over millions of years make northern plains fertile.

VI. Answer in a paragraph

Question 1.
India is a Sub-Continent. Prove it.
Answer:

1. Physical features
2. Climate conditions
3. Natural vegetation
4. Cultural norms
5. Ancient ethic and linguistic groups
6. Huge area

All these distinctive continental characteristic are found in India. Hence we consider India as a Sub-Continent.

Question 2.
Name the old fold mountain in India and write a brief note on it.
Answer:

1. Aravalli range is the old fold mountain in India.
2. These mountains are the relies and are reduced into hills due to erosional features.
3. The Aravalli hills form the North-Western and Western boundary of the Central Highlands a sub division of Peninsular plateau.
4. These hills extends from Gujarat through Rajasthan to Delhi in the North westerly direction (700km).
5. The height of these hills is about 1500m in South west and near Delhi hardly 400m.
6. Gurushikar (1722m) is the highest peak of this range.

Question 3.
Write a note on Purvanchal Hills.
Answer:

1. They are the eastern off-shoot of Himalayas.
2. It extended in the north-eastern states of India.
3. Most of these hills are located along the border of India and Myanmar while others are inside India.
4. Dafla Hills, Abor Hills, Mishmi Hills, Patkai Bum Hills, Naga Hills, Manipur Hills, Mizo Hills, Tripura Hills, Mikir Hills, Garo Hills, Khasi Hills and Jaintia Hills are the hills which are collectively known as Purvanchal Hills.

Question 4.
Write in general about the structure of the Peninsular plateau.
Answer:

1. The peninsular plateau lies to the south of the Great Northern plains.
2. This is the largest physiographic division covers an area of about 16 lakh sq.km.
3. It is made up of old rocks and consists of series of plateaus and hill ranges interspersed with river valleys.
4. The average height of a large portion of this plateau is more than 600m.
5. Anaimudi is the highest point of this place located in Anaimalai.
6. The plateau slopes towards east and is a part of ancient Gondwana.
7. River Narmada divides the Plateau region into two. The region lying to the north of Narmada is called Central Highlands and South of Narmada is called Deccan plateau.

VII. Map exercises

Question 1.
Mark the following in the outline map of India.

Set 1:

1. Mark the boundaries of India
2. Latitudinal Extent
3. Longitudinal Extent
4. Tropic of cancer
5. Lakshadweep Islands
6. Andaman and Nicobar Islands
   
7. Central Meridian of India
   

Set 2:
Peaks: Anaimudi, Mt. Everest, Mt.K2 Mahendragiri, Gurushikhar. NamchaBarwa, Nanga parbat, Kanchenjunga. Dhaulagiri, Makalu. Nandadevi, Dodabetta.

Hill stations: Shimla, Mussourie Ranikhet, Nainital, Almora, Darjeeling.

Hills: Aravalli, Vindhya. Satpura, Naga hills, Mizo hills, Garo hills, Khasi hills, Jaintia hills, Nilgiri hills, Anaimalai hills, Cardomom hills, Raj Mahal hills, Gir hills.

Gulf: Gulf of Mannar, Gulf of Kutch, Rann of Kutch, Palk Strait, Gulf of Cambay.

Set 3:
Seven Union Territories:

1. Delhi
2. Chandigarh
3. Diu and Daman
4. Dadra and Nagar Haveli
5. Pondicherry
6. Andaman and Nicobar Islands
7. Lakshadweep.