{"id":1771,"date":"2025-01-03T17:00:02","date_gmt":"2025-01-03T11:30:02","guid":{"rendered":"https:\/\/samacheerkalvi.guide\/?p=1771"},"modified":"2025-01-04T10:01:36","modified_gmt":"2025-01-04T04:31:36","slug":"tamil-nadu-12th-chemistry-model-question-paper-4-english-medium","status":"publish","type":"post","link":"https:\/\/samacheerkalvi.guide\/tamil-nadu-12th-chemistry-model-question-paper-4-english-medium\/","title":{"rendered":"Tamil Nadu 12th Chemistry Model Question Paper 4 English Medium"},"content":{"rendered":"

Students can Download Tamil Nadu 12th Chemistry Model Question Paper 4 English Medium Pdf, Tamil Nadu 12th Chemistry Model Question Papers<\/a> helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.<\/p>\n

TN State Board 12th Chemistry Model Question Paper 4 English Medium<\/h2>\n

Time: 3 Hours
\nMaximum Marks: 70<\/p>\n

Instructions:<\/p>\n

    \n
  1. The question paper comprises of four<\/span> parts<\/li>\n
  2. You are to attempt all the parts An internal choice of questions is provided wherever applicable<\/li>\n
  3. All questions of Part I, II, III, and IV are to be attempted separately<\/li>\n
  4. Question numbers 1 to 15<\/span> in Part I<\/span> are Multiple Choice Questions of one mark<\/span> 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<\/li>\n
  5. Question numbers 16 to 24<\/span> in Part II<\/span> are two-mark questions<\/span>. These are lo be answered in about one or two sentences<\/li>\n
  6. Question numbers 25 to 33<\/span> in Part III<\/span> are three-marks questions. <\/span>These are to be answered in about three to five short sentences<\/li>\n
  7. Question numbers 34 to 38<\/span> in Part IV <\/span>are five-mark<\/span> Questions These are to answered in detail. Draw diagrams wherever necessary<\/li>\n<\/ol>\n

    Part – 1<\/span><\/p>\n

    Answer all the questions. Choose the correct answer. [15 \u00d7 1 = 15]<\/span><\/p>\n

    Question 1.
    \nDepressing agents used to separate ZnS from PbS is …………..
    \n(a) NaCN
    \n(b) NaCl
    \n(c) NaNO3<\/sub>
    \n(d) NaNO2<\/sub>
    \nAnswer:
    \n(a) NaCN<\/p>\n

    Question 2.
    \nThe basic structural unit of silicates is
    \n(a)(SiO3<\/sub>)2-<\/sup>
    \n(b) (SiO4<\/sub>)2-<\/sup>
    \n(c) (SiO)–<\/sup>
    \n(d) (SiO4<\/sub>)4-<\/sup>
    \nAnswer:
    \n(d) (SiO4<\/sub>)4-<\/sup><\/p>\n

    \"Tamil<\/p>\n

    Question 3.
    \n………………… is a pungent smelling gas.
    \n(a) Ammonia
    \n(b) Nitric acid
    \n(c) Fluorite
    \n(d) Sodium chloride
    \nAnswer:
    \n(a) Ammonia<\/p>\n

    Question 4.
    \nConsider the following statement.
    \n(i) All the actinoids are non radioactive.
    \n(ii) Neptunium and other heavier elements are produced by artificial transformation of naturally occurring elements by nuclear reactions.
    \n(iii) Most.of the actinoids have long half lives.
    \nWhich of the above statements is\/are not correct.
    \n(a) i only
    \n(b) i and ii
    \n(c) ii and iii
    \n(d) i and iii
    \nAnswer:
    \n(d) i and iii<\/p>\n

    Question 5.
    \nHow many geometrical isomers are possible for [Pt (Py) (NH3<\/sub>) (Br) (Cl)]?
    \n(a) 3
    \n(b) 4
    \n(c) 0 3
    \n(d) 15
    \nAnswer:
    \n(a) 3<\/p>\n

    Question 6.
    \nMetal excess defect is possible in……………….
    \n(a) AgCl
    \n(b) AgBr
    \n(c) KCl
    \n(d) Fes
    \nAnswer:
    \n(c) KCl<\/p>\n

    Question 7.
    \nThe correct difference between first and second order reactions is that ……………………
    \n(a) A first order reaction can be catalysed; a second order reaction cannot be catalysed.
    \n(b) The half life of a first order reaction does not depend on [A0<\/sub>]; the half-life of a second order reaction does depend on [A0<\/sub>].
    \n(c) The rate of a first order reaction does not depend on reactant concentrations; the rate of a second order reaction does depend on reactant concentrations.
    \n(d) The rate of a first order reaction does depend on reactant concentrations; the rate of a second order reaction does not depend on reactant concentrations.
    \nAnswer:
    \n(b) The half life of a first order reaction does not depend on [A0<\/sub>]; the half-life of a second order reaction does depend on [A0<\/sub>].
    \nSolution:
    \nFor a first order reaction
    \n\"Tamil<\/p>\n

    Question 8.
    \nConcentration of the Ag+<\/sup> ions in a saturated solution of Ag2<\/sub>C2<\/sub>O4<\/sub> is 2.24 \u00d7 10-4<\/sup> mol L-1<\/sup> solubility product of Ag2<\/sub>C2<\/sub>O4<\/sub> is
    \n(a) 2.42 \u00d7 10-8<\/sup> mol3<\/sup> L-3<\/sup>
    \n(b) 2.66 \u00d7 10-12<\/sup>mol3<\/sup> L-3<\/sup>
    \n(c) 4.5 \u00d7 10-11<\/sup>mol3<\/sup> L-3<\/sup>
    \n(d) 5.619 \u00d7 10-12<\/sup>mol3<\/sup> L-3<\/sup>
    \nAnswer:
    \n(d) 5.619 \u00d7 10-12<\/sup>mol3<\/sup> L-3
    \n<\/sup>Solution:
    \n\"Tamil<\/p>\n

    \"Tamil<\/p>\n

    Question 9.
    \nAssertion(A): Copper Sulphate can be stored in a Zinc vessel.
    \nReason (R): Zinc is less reactive than Copper.
    \n(a) Both A and R are correct
    \n(b) Both A and R are wrong
    \n(c) A is correct but R is wrong
    \n(d) A is wrong but R is correct
    \nAnswer:
    \n(b) Both A and R are wrong<\/p>\n

    Question 10.
    \nFog is colloidal solution of……………..
    \n(a) solid in gas
    \n(b) gas in gas
    \n(c) liquid in gas
    \n(d) gas in liquid
    \nAnswer:
    \n(c) liquid in gas<\/p>\n

    dispersion medium-gas
    \ndispersed phase-liquid<\/p>\n

    Question 11.
    \nMatch the following Column-I with Column-II using the code given below.
    \nc\"Tamil
    \nAnswer:
    \n(a) A – 2,B – 3, C – 4, D – 1<\/p>\n

    Question 12.
    \n\"Tamil
    \n(a) anilinium chloride
    \n(b) O – nitro aniline
    \n(c) benzene diazonium chloride
    \n(d) m – nitro benzoic acid
    \n\"Tamil
    \nAnswer:
    \n(c) benzene diazonium chloride<\/p>\n

    Question 13.
    \nWhich one of the following is the IUPAC name of CH3<\/sub> – CH2<\/sub> – CH2<\/sub> CN?
    \n(a) Propiono nitrile
    \n(b) Butane cyanide
    \n(c) Isobutyro nitrile
    \n(d) Butane nitrile
    \nAnswer:
    \n(d) Butane nitrile<\/p>\n

    Question 14.
    \nThe correct corresponding order of names of four aldoses with configuration given below Respectively is ……………
    \n(a) L-Erythrose, L-Threose, L-Eiythrose, D-Threose
    \n(b) D-Threose, D-Erythrose, L-Threose, L-Erythrose
    \n(c) L-Erythrose, L-Threose, D-Erythrose, D-Threose
    \n(d) D-Erythrose, D-Threose, L-Erythrose, L-Threose
    \nAnswer:
    \n(d) D-Erythrose, D-Threose, L-Erythrose, L-Threose<\/p>\n

    Question 15.
    \nTranquilisers are substances used for the treatment of ………………
    \n(a) cancer
    \n(b) AIDS.
    \n(c) mental diseases
    \n(d) blood infection
    \nAnswer:
    \n(c) mental diseases<\/p>\n

    Part – II<\/span><\/p>\n

    Answer any six questions. Question No. 22 is compulsory. [6 \u00d7 2 = 12]<\/span><\/p>\n

    Question 16.
    \nWhat are leaching process?
    \nAnswer:
    \nThis method is based on the solubility of the ore in a suitable solvent and the reactions in aqueous solution. In this method, the crushed ore is allowed to dissolve in a suitable solvent, the metal present in the ore is converted to its soluble salt or complex while the gangue remains insoluble. This process is also called chemical method.<\/p>\n

    \"Tamil<\/p>\n

    Question 17.
    \nWhat happens when PCI5 is heated?
    \nAnswer:
    \nOn heating phosphorous pentachloride, it decomposes into phosphorus trichloride and chlorine.
    \n\"Tamil<\/p>\n

    Question 18.
    \nWrite the biologically importance of coordination compounds.
    \nAnswer:
    \nBiological important of coordination compounds:<\/p>\n

    (i) Ared blood corpuscles (RBC) is composed of heme group, which is Fe2+<\/sup>– Porphyrin complex, it plays an important role in carrying oxygen from lungs to tissues and carbon dioxide from tissues to lungs.<\/p>\n

    (ii) Chlorophyll, a green pigment present in green plants and algae, is a coordination complex containing Mg2+<\/sup> as central metal ion surrounded by a modified Porphyrin ligand called corrin ring. It plays an important role in photosynthesis, by which plants converts CO2<\/sub> and water into carbohydrates and oxygen.<\/p>\n

    (iii) Vitamin B12<\/sub>(cyanocobalamine) is the only vitamin consist of metal ion. it is a coordination complex in which the central metal ion is CO+<\/sup> surrounded by Porphyrin like ligand.<\/p>\n

    (iv) Many enzymes are known to be metal complexes, they regulate biological processes. For example, Carboxypeptidase is a protease enzyme that hydrolytic enzyme important in digestion, contains a zinc ion coordinated to the protein.<\/p>\n

    Question 19.
    \nMention the factors affecting the reaction rate.
    \nAnswer:
    \nThe rate of the reaction is affected by the following factors.<\/p>\n