{"id":37348,"date":"2024-02-21T03:20:37","date_gmt":"2024-02-20T21:50:37","guid":{"rendered":"https:\/\/samacheerkalvi.guide\/?p=37348"},"modified":"2024-02-21T16:38:26","modified_gmt":"2024-02-21T11:08:26","slug":"samacheer-kalvi-11th-chemistry-guide-chapter-14","status":"publish","type":"post","link":"https:\/\/samacheerkalvi.guide\/samacheer-kalvi-11th-chemistry-guide-chapter-14\/","title":{"rendered":"Samacheer Kalvi 11th Chemistry Guide Chapter 14 Haloalkanes and Haloarenes"},"content":{"rendered":"

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Chemistry Guide<\/a> Pdf Chapter 14 Haloalkanes and Haloarenes Text Book Back Questions and Answers, Notes.<\/p>\n

Tamilnadu Samacheer Kalvi 11th Chemistry Solutions Chapter 14 Haloalkanes and Haloarenes<\/h2>\n

11th Chemistry Guide Haloalkanes and Haloarenes Text Book Back Questions and Answers<\/h3>\n

Textbook Evaluation:<\/span><\/p>\n

I. Choose the best answer:<\/span><\/p>\n

Question 1.
\nThe IUPAC name of \"Samacheer is
\na) 2 – Bromo pent – 3 – ene
\nb) 4 – Bromo pent – 2 – ene
\nc) 2 – Bromo pent – 4 – ene
\nd) 4 – Bromo pent – 1 – ene
\nAnswer:
\nb) 4 – Bromo pent – 2 – ene<\/p>\n

Question 2.
\nOf the following compounds, which has the highest boiling point?
\na) n – Butyl chloride
\nb) Isobutyl chloride
\nc) t – Butyl chloride
\nd) n – Propyl chloride
\nAnswer:
\na) n – Butyl chloride<\/p>\n

Question 3.
\nArrange the following compounds in increasing order of their density
\nA) CCl4<\/sub>
\nB) CHCl3<\/sub>
\nC) CH2<\/sub>Cl2<\/sub>
\nD) CH3<\/sub>Cl
\na) D < C < B < A
\nb) C > B > A > D
\nc) A < B < C < D
\nd) C > A > B > D
\nAnswer:
\na) D < C < B < A<\/p>\n

Question 4.
\nWith respect to the position of – Cl in the compound CH3 – CH = CH – CH2<\/sub> – Cl, it is classified as
\na) Vinyl
\nb) Allyl
\nc) Secondary
\nd) Aralkyl
\nAnswer:
\nb) Allyl<\/p>\n

Question 5.
\nWhat should be the correct IUPAC name of diethyl chloromethane?
\na) 3 – Chloro pentane
\nb) 1 – Chloropentane
\nc) 1 – Chloro – 1, 1 – diethyl methane
\nd) 1- Chloro-1-ethyl propane
\nAnswer:
\na) 3 – Chloro pentane<\/p>\n

\"Samacheer<\/p>\n

Question 6.
\nC – X bond is strongest in
\na) Chloromethane
\nb) Iodomethane
\nc) Bromomethane
\nd) Fluoromethane
\nAnswer:
\nd) Fluoromethane<\/p>\n

Question 7.
\nIn the reaction \"Samacheer X is ______.<\/p>\n

\"Samacheer
\nAnswer:
\nb) \"Samacheer<\/p>\n

Question 8.
\nWhich of the following compounds will give racemic mixture on nucleophilic substitution by OH–<\/sup> ion?
\ni) \"Samacheer<\/p>\n

ii) \"Samacheer<\/p>\n

iii) \"Samacheer
\na) (i)
\nb) (ii) and (iii)
\nc) (iii)
\nd) (i) and (ii)
\nAnswer:
\nc) (iii)<\/p>\n

Question 9.
\nThe treatment of ethyl formate with excess of RMgX gives
\na) \"Samacheer<\/p>\n

b) \"Samacheer
\nc) R – CHO
\nd) R – O – R
\nAnswer:
\nc) R – CHO<\/p>\n

Question 10.
\nBenzene reacts with Cl2<\/sub> in the presence of FeCl3<\/sub> and in absence of sunlight to form
\na) Chlorobenzene
\nb) Benzyl chloride
\nc) Benzal chloride
\nd) Benzene hexachloride
\nAnswer:
\na) Chlorobenzene<\/p>\n

\"Samacheer<\/p>\n

Question 11.
\nThe name of C2<\/sub>F4<\/sub>C12<\/sub> is
\na) Freon – 112
\nb) Freon – 113
\nc) Freon – 114
\nd) Freon – 115
\nAnswer:
\nc) Freon – 114<\/p>\n

Question 12.
\nWhich of the following reagent is helpful to differentiate ethylene dichloride and ehtylidene chloride?
\na) Zn \/ methanol
\nb) KQH \/ ethanol
\nc) aqueous KOH
\nd) ZnCl2<\/sub> \/ Con HCl
\nAnswer:
\nc) aqueous KOH<\/p>\n

Question 13.
\nMatch the compounds given in Column I with suitable items given in Column II:<\/p>\n\n\n\n\n\n\n\n
Column I (Compound)<\/td>\nColumn II (Uses)<\/td>\n<\/tr>\n
A. Iodoform<\/td>\n1. Fire extinguisher<\/td>\n<\/tr>\n
B. Carbon tetra chloride<\/td>\n2. Insecticide<\/td>\n<\/tr>\n
C. CFC<\/td>\n3. Antiseptic<\/td>\n<\/tr>\n
D. DDT<\/td>\n4. Refrigerants<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Code
\na) A \u2192 2 B \u2192 4 C \u2192 1 D \u2192 3
\nb) A \u2192 3 B \u2192 2 C \u2192 4 D \u2192 1
\nc) A \u2192 1 B \u2192 2 C \u2192 3 D \u2192 4
\nd) A \u2192 3 B \u2192 1 C \u2192 4 D \u2192 2
\nAnswer:
\nd) A \u2192 3 B \u2192 1 C \u2192 4 D \u2192 2<\/p>\n

Question 14.
\nAssertion:
\nInmonohaloarenes, electrophilic substitution occurs at ortho and para positions.
\nReason:
\nHalogen atom is a ring deactivator.
\nAssertion and Reason type questions.
\nDirections:
\nIn the following questions, a statement of assertion (A) is followed by a statement of reason (R) mark the correct choice as
\n(i) If both assertion and reason are true and reason is the correct explanation of assertion.
\n(ii) If both assertion and reason are true but reason is not the correct explanation of assertion.
\n(iii) If assertion is true but reason is false.
\n(iv) If both assertion and reason are false.
\na) (i)
\nb) (ii)
\nc) (iii)
\nd) (iv)
\nAnswer:
\nb) (ii)<\/p>\n

Question 15.
\nConsider the reaction,
\nCH3<\/sub>CH2<\/sub>CH2<\/sub>Br + NaCN \u2192 CH3<\/sub>CH2<\/sub>CH2<\/sub>CN + NaBr This reaction will be the fastest in
\na) ethanol
\nb) methanol
\nc) DMF (N, N’ – dimethyl formamide)
\nd) water
\nAnswer:
\nc) DMF (N, N’ – dimethyl formamide)<\/p>\n

\"Samacheer<\/p>\n

Question 16.
\nFreon – 12 manufactured from tetrachloro methane by
\na) Wurtz reaction
\nb) Swarts reaction
\nc) Haloform reaction
\nd) Gattermann reaction
\nAnswer:
\nb) Swarts reaction<\/p>\n

Question 17.
\nThe most easily hydrolysed molecules under SN1<\/sup><\/sub> condition is
\na) allyl chloride
\nb) ethyl chloride
\nc) isopropyl chloride
\nd) benzyl chloride
\nAnswer:
\na) allyl chloride<\/p>\n

Question 18.
\nThe carbon cation formed in SN1<\/sup><\/sub>\u00a0reaction of alkyl halide in the slow step is
\na) sp3<\/sup> hybridized
\nb) sp2<\/sup> hybridized
\nc) sp hybridized
\nd) none of these
\nAnswer:
\nb) sp2<\/sup> hybridized<\/p>\n

Question 19.
\nThe major products obtained when chlorobenzene is nitrated with HNO3<\/sub> and con H2<\/sub>SO4<\/sub>
\na) 1 – chloro – 4 – nitrobenzene
\nb) 1 – chloro – 2 – nitrobenzene
\nc) 1 – chloro – 3 – nitrobenzene
\nd) 1 – chloro – 1 – nitrobenzene
\nAnswer:
\na) 1 – chloro – 4 – nitrobenzene<\/p>\n

Question 20.
\nWhich one of the following is most reactive towards nucleophilic substitution reaction?
\na) \"Samacheer<\/p>\n

b) \"Samacheer<\/p>\n

c) \"Samacheer<\/p>\n

d) \"Samacheer
\nAnswer:
\nd) \"Samacheer<\/p>\n

\"Samacheer<\/p>\n

Question 21.
\nEthylidene chloride on treatment with aqueous KOH gives
\na) acetaldehyde
\nb) ethylene glycol
\nc) formaldehyde
\nd) glycoxal
\nAnswer:
\na) acetaldehyde<\/p>\n

Question 22.
\nThe raw material for Raschig process
\na) chloro benzene
\nb) phenol
\nc) benzene
\nd) anisole
\nAnswer:
\nc) benzene<\/p>\n

Question 23.
\nChloroform reacts with nitric acid to produce
\na) nitro toluene
\nb) nitro glycerine
\nc) chloropicrin
\nd) chloropicric acid
\nAnswer:
\nc) chloropicrin<\/p>\n

Question 24.
\nAcetone \"Samacheer X, X is
\na) 2 – propanol
\nb) 2 – methyl – 2 – propanol
\nc) 1 – propanol
\nd) acetonol
\nAnswer:
\nb) 2 – methyl – 2 – propanol<\/p>\n

Question 25.
\nSilverpropionate when refluxed with Bromine in carbon tetrachloride gives
\na) propionic acid
\nb) chloroethane
\nc) Bromo ethane
\nd) chloro propane
\nAnswer:
\nc) bromo ethane<\/p>\n

\"Samacheer<\/p>\n

II. Write brief answer to the following questions:<\/span><\/p>\n

Question 26.
\nClassify the following compounds in the form of alkyl, allylic, vinyl, benzylic halides.
\ni) CH3<\/sub> – CH = CH – Cl<\/p>\n

ii) C6<\/sub>H5<\/sub>CH2<\/sub>I<\/p>\n

iii) \"Samacheer<\/p>\n

iv) CH2<\/sub> = CH – Cl
\nAnswer:
\ni) CH3<\/sub> – CH = CH – Cl = Allylic halide<\/p>\n

ii) C6<\/sub>H5<\/sub>CH2<\/sub>I = Benzylic halide<\/p>\n

iii) \"Samacheer = Alkyl halide<\/p>\n

iv) CH2<\/sub> = CH – Cl = Vinyl halide<\/p>\n

Question 27.
\nWhy chlorination of methane is not possible in dark?
\nAnswer:<\/p>\n

    \n
  • Chlorination of methane is a free radical substitution reaction.<\/li>\n
  • Before chlorine reacts with methane, the Cl-Cl single bond must break to form free radicals and this can only be done in the presence of ultraviolet light.<\/li>\n
  • In dark, chlorine-free radicals formation is not possible and so chlorination of methane is not possible in dark.<\/li>\n
  • The ultraviolet light is a source of energy and is being used to break of Cl-Cl and produce Cl free radical Free radicals which can attack methane. in dark, this is not possible.<\/li>\n<\/ul>\n

    Question 28.
    \nHow will you prepare n propyl iodide from n – propyl bromide?
    \nAnswer:
    \nFinkelstein reaction,
    \nnCH3<\/sub> – CH2<\/sub> – CH2<\/sub> – Br + NaI \"Samacheer n – CH3<\/sub> – CH2<\/sub> – CH2<\/sub> – I + NaBr
    \nn – propyl iodide\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 n- propyl bromide<\/p>\n

    Question 29.
    \nWhich alkyl halide from the following pair is
    \ni) chiral
    \nii) undergoes faster SN2<\/sup><\/sub> reaction?
    \n\"Samacheer
    \nAnswer:
    \n\"Samacheer
    \nIt contains one chiral carbon atom.
    \n2 – Bromo butane undergoes SN2<\/sup><\/sub> mechanism faster than 1- Chloro butane.<\/p>\n

    Question 30.
    \nHow does chlorobenzene react with sodium in the presence of ether? What is the name of the reaction?
    \nAnswer:
    \nHaloarenes react with sodium metal in dry ether, two aryl groups combine to give biaryl products.
    \nThis reaction is called fittig reaction.
    \nC6<\/sub>H5<\/sub>Cl + 2Na + Cl – C6<\/sub>H5<\/sub> \"Samacheer C6<\/sub>H5<\/sub> – C6<\/sub>H5<\/sub> + 2NaCl
    \nChlorobenzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Biphenyl<\/p>\n

    \"Samacheer<\/p>\n

    Question 31.
    \nGive reasons for the polarity of C – X bond in haloalkane.
    \nAnswer:
    \nCarbon halogen bond is a polar bond as halogens are more electronegative than carbon. The carbon atom exhibits a partial positive charge (\u03b4+<\/sup>) and halogen atom a partial negative charge (\u03b4–<\/sup>)
    \n\"Samacheer<\/p>\n

    The C -X bond is formed by overlap of sp3<\/sup> orbital of a carbon atom with half-filled p- orbital of the halogen atom. The atomic size of halogen increases from fluorine to iodine, which increases the C – X bond length. Larger the size, greater is the bond length, and the weaker is the bond formed. The bond strength of C – X decreases from C – F to C – I in CH3<\/sub>X.<\/p>\n

    Question 32.
    \nWhy is it necessary to avoid even traces of moisture during the use of Grignard reagent?
    \nAnswer:
    \nGrignard reagents are mostly reactive and react with the source of the product to give hydrocarbons. Even alcohols, amines, H2<\/sub>O are sufficiently acidic to convert them to corresponding hydrocarbons.
    \nR Mg X + H2<\/sub>O \u2192 RH + \"Samacheer<\/p>\n

    Due to its high reactivity, it is necessary to avoid even traces of moisture from the Grignard reagent.<\/p>\n

    Question 33.
    \nWhat happens when acetyl chloride is treated with an excess of CH3<\/sub>MgI?
    \nAnswer:
    \n\"Samacheer<\/p>\n

    \"Samacheer<\/p>\n

    Question 34.
    \nArrange the following alkyl halide in increasing order of bond enthalpy of RX.
    \nCH3<\/sub>Br, CH3<\/sub>F, CH3<\/sub>Cl, CH3<\/sub>I
    \nAnswer:
    \nThe order is:
    \nCH3<\/sub>I < CH3<\/sub>Br < CH3<\/sub>Cl < CH3<\/sub>F.<\/p>\n

    Question 35.
    \nWhat happens when chloroform reacts with oxygen in the presence of sunlight?
    \nAnswer:
    \n2 CHCl3<\/sub> + O2<\/sub> \u2192 2 COCl2<\/sub> + 2 HCl<\/p>\n

    \"Samacheer<\/p>\n

    Question 36.
    \nWrite down the possible isomers of C5<\/sub>H11<\/sub>Br and give their IUPAC and common names.
    \nAnswer:
    \nC5<\/sub>H11<\/sub>Br – Possible isomers
    \n1. CH3<\/sub> – CH2<\/sub> – CH2<\/sub> – CH2<\/sub> – CH2<\/sub> – Br \u2192 1 – bromo pentane<\/p>\n

    2. \"Samacheer \u2192 2 – bromo pentane<\/p>\n

    3. \"Samacheer \u2192 3 – bromo pentane<\/p>\n

    4.\u00a0 \"Samacheer \u2192 1 – bromo 2, 2 – dimethyl propane<\/p>\n

    5. \"Samacheer \u2192 1 – bromo 3 – methyl butane<\/p>\n

    6. \"Samacheer \u2192 2 – bromo 3 – methyl butane<\/p>\n

    7. \"Samacheer \u2192 2 – bromo 2 – methyl butane<\/p>\n

    8. \"Samacheer \u2192 1 – bromo 2- methyl butane<\/p>\n

    9. \"Samacheer \u2192 (2S) – 1 – bromo 2 – methyl butane<\/p>\n

    10. \"Samacheer \u2192 (2R) – 1 – bromo 2 – methyl butane<\/p>\n

    Question 37.
    \nMention any three methods of preparation of haloalkanes from alcohols.
    \nAnswer:
    \nHaloalkanes are prepared by the following methods.
    \nFrom alcohols: Alcohol can be converted into halo alkenes by reacting it with any one of the following reagents.<\/p>\n

      \n
    • Hydrogen halide<\/li>\n
    • Phosphorous halides<\/li>\n
    • Thionyl chloride.<\/li>\n<\/ul>\n

      a) Reaction with hydrogen halide:
      \n\"Samacheer<\/p>\n

      Mixture of con. HCl and anhydrous ZnCl2<\/sub> is called Lucas Reagent.<\/p>\n

      \"Samacheer<\/p>\n

      The order of reactivity of halo acids with alcohol is in the order HI > HBr > HCl.
      \nThe order of reactivity of alcohols with halo acid is tertiary > secondary > primary.<\/p>\n

      b) Reaction with phosphorous halides:
      \nAlcohols react with PX5<\/sub> or PX3<\/sub> to form haloalkanes.
      \nExample:
      \nCH3<\/sub>CH2<\/sub>OH + PCl5<\/sub> \u2192 CH3<\/sub>CH2<\/sub>Cl + POCl3<\/sub> + HCl
      \nEthane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Chloro ethane<\/p>\n

      3CH3<\/sub>CH2<\/sub>OH + PCl3<\/sub> \u2192 3 CH3<\/sub>CH2<\/sub>Cl + H3<\/sub>PO3<\/sub>
      \nEthanol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Chloro ethane<\/p>\n

      c) Reaction with Thionyl chloride(Sulphonyl Chloride)
      \nCH3<\/sub>CH3<\/sub>OH + SOCl2<\/sub> \"Samacheer CH3<\/sub>CH2<\/sub>Cl + SO2<\/sub>\u2191 + HCl\u2191
      \nEthanol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Chloro ethane<\/p>\n

      Question 38.
      \nCompare SN1<\/sup><\/sub> and SN2<\/sup><\/sub> reaction mechanisms.
      \nAnswer:<\/p>\n\n\n\n\n\n\n\n\n\n
      <\/td>\nSN<\/sub>1<\/sup><\/td>\nSN<\/sub>2<\/sup><\/td>\n<\/tr>\n
      Rate law<\/td>\nUnimolecular (Substrate only)<\/td>\nBiomolecular (substrate and nucleophile)<\/td>\n<\/tr>\n
      \u201cBig Barrier\u201d<\/td>\nCarbocation stability<\/td>\nSteric hindrance<\/td>\n<\/tr>\n
      Alkyl halide (electrophile)<\/td>\n3\u00b0 > 2\u00b0 > 1\u00b0<\/td>\n\u00a01\u00b0 > 2\u00b0 > 3\u00b0<\/td>\n<\/tr>\n
      Nucleophile<\/td>\nWeak (generally neutral)<\/td>\nStrong (generally bearing a negative charge)<\/td>\n<\/tr>\n
      Solvent<\/td>\nPolar protic (e.g., alcohols)<\/td>\nPolar aprotic (e.g., DMSO, acetone)<\/td>\n<\/tr>\n
      Stereo Chemistry<\/td>\nMix of retention and inversion<\/td>\ninversion<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      Question 39.
      \nReagents and the conditions used in the reactions are given below. Complete the table by writing down the product and the name of the reaction.
      \n\"Samacheer
      \nAnswer:
      \n\"Samacheer<\/p>\n

      Question 40.
      \nDiscuss the aromatic nucleophilic substitutions reaction of chlorobenzene.
      \nAnswer:
      \nThe halogen of haloarenes can be substituted by OH–<\/sup>, NH2<\/sub>–<\/sup> or CN–<\/sup> with appropriate nucleophilic reagents at high temperature and pressure.
      \nExample:
      \n(i) Chlorobenzene reacts with ammonium at 250 and at 50 atm to give aniline.
      \nC6<\/sub>H5<\/sub>Cl + 2NH3<\/sub> \"Samacheer C6<\/sub>H5<\/sub>NH2<\/sub> + NH4<\/sub>Cl
      \nChlorobenzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Aniline<\/p>\n

      (ii) Chlorobenzcne reacts with CuCN in presence of pyridine at 250 to give phenyl cyanide.
      \nC6<\/sub>H5<\/sub>Cl + CuCN \"Samacheer C6<\/sub>H5<\/sub>CN + CuCl
      \nChlorobenzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Phenyl cyanide<\/p>\n

      (iii) Dows process:
      \nC6<\/sub>H5<\/sub>Cl + NaOH \"Samacheer C6<\/sub>H5<\/sub>OH + NaCl
      \nChlorobenzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Phenol
      \nThis reaction is known as Dow\u2019s process.<\/p>\n

      \"Samacheer<\/p>\n

      Question 41.
      \nAccount for the following:
      \n(i) t – butyl chloride reacts with aqueous KOH by SN1<\/sup><\/sub> mechanism while n – butyl chloride reacts with SN2<\/sup><\/sub> mechanism.
      \n(ii) p – dichlorobenzene has a higher melting point than those of o – and m – dichlorobenzene.
      \nAnswer:
      \n(i) t – butyl chloride reacts with aqueous KOH by SN1<\/sup><\/sub> mechanism while n – butyl chloride reacts with SN2<\/sup><\/sub> mechanism.
      \nIn general, the SN1<\/sup><\/sub> reaction proceeds through the formation, of carbocation, The tert-butyl chloride readily loses Cl ion to form stable 3\u00b0 carbocation. Therefore, it reacts with aqueous KOH by SN1<\/sup><\/sub> mechanism as:
      \n\"Samacheer<\/p>\n

      On the other hand, n-Butyl chloride does not undergo ionization to form n-Butyl carbocation (1\u00b0) because it is not stable. Therefore, it prefers to undergo reaction by an SN2<\/sup><\/sub> mechanism, which occurs is one step through a transition state involving the nucleophilic attack of OH–<\/sup> ion from the backside with simultaneous expulsion of Cl–<\/sup> ion from the front side.
      \n\"Samacheer<\/p>\n

      SN1<\/sup><\/sub> mechanism follows the reactivity order as 3\u00b0 > 2\u00b0> 1\u00b0 while SN2<\/sup><\/sub> mechanism follows the reactivity order as 1\u00b0 > 2\u00b0 > 3\u00b0. Therefore, tert-butyl chloride (3\u00b0) reacts by SN1<\/sup><\/sub> mechanism while n-butyl chloride (1\u00b0) reacts by an SN2 <\/sup><\/sub>mechanism. (ii) p – dichlorobenzene has a higher melting point than those of o – and m – dichloro benzene. The higher melting point of p – isomer is due to its symmetry which leads to more close packing of its molecules in the crystal lattice and consequently strong intermolecular attractive force which requires more energy for melting. p – Dihalo benzene > o – Dichloro benzene> m – Dichioro benzene
      \nMelting point: 323 K 256 K 249 K<\/p>\n

      Question 42.
      \nIn an experiment methyl iodide in ether is allowed to stand over magnesium pieces. Magnesium dissolves and product is formed.
      \na) Name of the product and write the equation for the reaction.
      \nb) Why all the reagents used in the reaction should be dry? Explain.
      \nc) How is acetone prepared from the product obtained in the experiment?
      \nAnswer:
      \na) Name of the product and write the equation for the reaction.
      \nCH3<\/sub>I + Mg \"Samacheer CH3<\/sub>MgI<\/p>\n

      b) Why all the reagents used in the reaction should be dry? Explain.
      \nAll the reagents used in the reaction should be dry because reagent reacts with H20 to produce alkane. This is the reason that everything has to be very dry during the preparation of Grignard reagents.
      \nCH3<\/sub> – MgI + H2<\/sub>O \u2192 CH4<\/sub> +\"Samacheer
      \nMethane<\/p>\n

      c) How is acetone prepared from the product obtained in the experiment?
      \n\"Samacheer<\/p>\n

      Question 43.
      \nWrite a chemical reaction useful to prepare the following.
      \ni) Freon – 12 from Carbon tetrachloride
      \nii) Carbon tetrachloride from carbon disulphide.
      \nAnswer:
      \ni) Freon – 12 from Carbon tetrachloride:
      \nFreon – 12 is prepared by the action of hydrogen fluoride on carbon tetrachloride in the presence of catalytic amount of antimony pentachloride.
      \nCCl4<\/sub> + 2HF \"Samacheer 2HCl + CCl2<\/sub>F2<\/sub>
      \nCarbon tetrachloride\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Freon – 12<\/p>\n

      ii) Carbon tetrachloride from carbon disulphide.
      \nCarbon disulphide reacts with chlorine gas in the presence of anhydrous AlCl3 as catalyst giving carbon tetrachloride.
      \nCS2<\/sub> + 3 Cl2<\/sub> \"Samacheer CCl4<\/sub> + S2<\/sub>Cl2<\/sub>
      \nCarbon disulfide\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Carbon tetrachloride<\/p>\n

      Question 44.
      \nWhat are Freons? Discuss their uses and environmental effects.
      \nAnswer:
      \nThe chloro fluoro derivatives of methane and ethane are called freons.
      \nNomenclature:
      \nFreon is represented as Freon – cba
      \nWhere a = number of carbon atoms – 1;
      \nb = number of hydrogen atoms + 1
      \na = total number of fluorine atoms
      \n\"Samacheer<\/p>\n

      Uses:<\/p>\n

        \n
      • Freons are used as a refrigerant in refrigerators and air conditioners.<\/li>\n
      • It is used as a propellant for aerosols and foams<\/li>\n
      • It is used as a propellant for foams to spray out deodorants, shaving creams, and insecticides.<\/li>\n<\/ul>\n

        Question 45.
        \nPredict the products when Bromo ethane is treated with the following.
        \ni) KNO2<\/sub>
        \nii) AgNO2<\/sub>
        \nAnswer:
        \ni) KNO2<\/sub>:
        \nBromo ethane reacts with an alcoholic solution of NaNO2 or KNO2 to form ethyl nitrite.
        \nCH3<\/sub>CH2<\/sub>Br + KNO2<\/sub> \u2192 CH3<\/sub>CH2<\/sub> – O – N = O + KBr
        \nBromoethane Ethyl nitrite<\/p>\n

        ii)AgNO2<\/sub>:
        \nBromo ethane reacts with an alcoholic solution of AgNO2 to form nitroethane.
        \nCH3<\/sub>CH2<\/sub>Br + AgNO2<\/sub> \u2192 CH3<\/sub>CH2<\/sub> NO2<\/sub> + AgBr
        \nBromoethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Nitroethane<\/p>\n

        \"Samacheer<\/p>\n

        Question 46.
        \nExplain the mechanism of SN1<\/sup><\/sub> reaction by highlighting the stereochemistry behind it.
        \nAnswer:
        \n\"Samacheer
        \nIn SN1<\/sup><\/sub> reactions, if the alkyl halide is optically active, the product obtained in a racemic mixture. The intermolecular carbocation formed in slowest step being sp2 hybridized is planar species. Therefore the attack of the nucleophile OH on it, can occur from both the faces with equal case forming a mixture of two enantiomers. Thus SN1<\/sup><\/sub> reaction of optically active alkyl halides is accompanied by racemization.<\/p>\n

        Question 47.
        \nWrite short notes on the following.
        \ni) Raschig process
        \nii) Dows process
        \niii) Darzen\u2019s process
        \nAnswer:
        \ni) Raschig process:
        \nChloro benzene is commercially prepared by passing a mixture of benzene vapour, air and HCl overheated cupric chloride, this reaction is called the Raschig process,
        \n\"Samacheer<\/p>\n

        ii) Dows Process:
        \nC6<\/sub>H5<\/sub>Cl + NaOH \"Samacheer C6<\/sub>H5<\/sub>OH + NaCl
        \nThis reaction is known as Dows process.<\/p>\n

        iii) Darzen\u2019s process:
        \nCH3<\/sub>CH2<\/sub>OH + SOCl \"Samacheer CH3<\/sub>CH2<\/sub>Cl + SO2<\/sub>\u2191 + HCl\u2191
        \nEthanol Chloro ethane
        \nThis reaction is known as Darzen’s process.<\/p>\n

        Question 48.
        \nStarting from CH3<\/sub>MgI, How will you prepare the following?
        \ni) Acetic acid
        \nii) Acetone
        \niii) Ethyl acetate
        \niv) Isopropyl alcohol
        \nv) Methyl cyanide
        \nAnswer:
        \ni) Acetic acid:
        \nSolid carbon dioxide reacts with methyl magnesium iodide to form additional product which on hydrolysis yields acetic acid.
        \n\"Samacheer<\/p>\n

        ii) Acetone:
        \nAcetyl chloride reacts with methyl magnesium iodide and followed by acid hydrolysis to give acetone.
        \n\"Samacheer<\/p>\n

        iii) Ethyl Acetate:
        \nEthyl chloroformate reacts with methyl magnesium iodide to form ethyl acetate.
        \n\"Samacheer<\/p>\n

        iv) Isopropyl alcohol:
        \nAldehydes (Acetaldehyde) other than formaldehyde, react with methyl magnesium iodide to give additional product which on hydrolysis yields isopropyl alcohol.
        \n\"Samacheer<\/p>\n

        v) Methyl cyanide:
        \nMethyl magnesium iodide reacts with cyanogen chloride to give methyl cyanide.
        \n\"Samacheer<\/p>\n

        \"Samacheer<\/p>\n

        Question 49.
        \nComplete the following reactions.
        \ni) CH3<\/sub> – CH = CH2<\/sub> + HBr \"Samacheer
        \nii) CH3<\/sub> – CH2<\/sub> – Br + NaSH \"Samacheer
        \niii) C6<\/sub>H5<\/sub>Cl + Mg \"Samacheer
        \niv) CHCl3<\/sub> + HNO3<\/sub> \"Samacheer
        \nv) CCl4<\/sub> + H2<\/sub>O \"Samacheer
        \nAnswer :
        \ni) CH3<\/sub> – CH = CH2<\/sub> + HBr \"Samacheer CH3<\/sub> – CH2<\/sub> – CH2<\/sub> – Br
        \nPropene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0n – propyl bromide<\/p>\n

        ii) CH3<\/sub> – CH2<\/sub> – Br + NaSH \"Samacheer CH3<\/sub> – CH2<\/sub> – SH + NaBr
        \nPropyl bromide\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethanethiol<\/p>\n

        iii) C6<\/sub>H5<\/sub>Cl (Chloro benzene) + Mg \"Samacheer C6<\/sub>H5<\/sub>MgCl (Phenyl magnesium chloride)<\/p>\n

        iv) CHCl3<\/sub> + HNO3<\/sub> \"Samacheer CCl3<\/sub>NO2<\/sub> + H
        \nChloroform\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Chloropicrin<\/p>\n

        v) CCl4<\/sub> (Carbon tetrachloride) + H2<\/sub>O \"SamacheerCOCl2<\/sub> (Carbonyl chloride) + 2HCl<\/p>\n

        Question 50.
        \nExplain the preparation of the following compounds.
        \ni) DDT
        \nii) Chloroform
        \niii) Biphrnyl
        \niv) Chloropicrin
        \nv) Freon – 12
        \nAnswer:
        \ni) DDT:
        \nDDT can be prepared by heating a mixture of chlorobenzene with chloral (Trichloro acetaldehyde) in the presence of con.H2<\/sub>SO4<\/sub>.
        \n\"Samacheer<\/p>\n

        ii) Chloroform:
        \nPreparation:
        \nChloroform is prepared in the laboratory by the reaction between ethyl alcohol with bleaching powder followed by the distillation of the product chloroform. Bleaching powder act as a source of chlorine and calcium hydroxide. This reaction is called the haloform reaction. The reaction proceeds in three steps as shown below.<\/p>\n

        Step – 1: Oxidation
        \nCH3<\/sub>CH2<\/sub>OH + Cl2<\/sub> \u2192 CH3<\/sub>CHO + 2HCl
        \nEthyl alcohol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethanal (Acetaldehyde)<\/p>\n

        Step – 2: Chlorination
        \nCH3<\/sub>CHO + 3Cl2<\/sub> \u2192 CCl3<\/sub>CHO + 3HCl
        \nAcetaldehyde\u00a0 \u00a0 \u00a0 \u00a0 Trichloro acetaldehyde<\/p>\n

        Step – 3: Hydrolysis
        \n2CCl3<\/sub>CHO + Ca(OH)2<\/sub> \u2192 2CHCl3<\/sub> + (HCOO)2<\/sub> Ca
        \nChloral\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0chloroform<\/p>\n

        iii) Biphenyl:
        \nChloro benzene reacts with sodium metal in dry ether, to give biphenyl. This reaction is called a fitting reaction.
        \nC6<\/sub>H5<\/sub>Cl + 2 Na + Cl – C6<\/sub>H5<\/sub> \"Samacheer C6<\/sub>H5<\/sub> – C6<\/sub>H5<\/sub> + 2NaCl
        \nChloro benzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Biphenyl<\/p>\n

        iv) Chloropicrin:
        \nChloroform reacts with nitric acid to form chloropicrin. (Trichloro nitromethane)
        \nCHCl3<\/sub> + HNO3<\/sub> \"Samacheer CCl3<\/sub>NO2<\/sub> + H2<\/sub>O
        \nChloroform\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Chloropicrin<\/p>\n

        v) Freon – 12
        \nFreon – 12 is prepared by the action of hydrogen fluoride on carbon tetrachloride in the presence of the catalytic amount of antimony pentachloride
        \nCCl4<\/sub> + 2 HF \"Samacheer 2 HCl + CCl2<\/sub>F2<\/sub>
        \nCarbon tetrachloride\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Freon – 12<\/p>\n

        \"Samacheer<\/p>\n

        Question 51.
        \nAn organic compound (A) with molecular formula C2<\/sub>H5<\/sub>Cl reacts with KOH gives compounds (B) and with alcoholic KOH gives compound (C). Identify (A), (B), (C).
        \nAnswer:
        \n\"Samacheer<\/p>\n

        Question 52.
        \nThe simplest alkene (A) reacts with HCl to form compound (B). Compound (B) reacts with ammonia to form compound (C) of molecular formula C2<\/sub>H7<\/sub>N. Compound (C) undergoes carbylamine test. Identify (A),
        \n(B) and (C).
        \nAnswer:
        \nCH2<\/sub> = CH2<\/sub> + HCl \u2192 C2<\/sub>H5<\/sub>Cl
        \n(A) Ethylene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 (B) Ethyl chloride<\/p>\n

        C2<\/sub>H5<\/sub>Cl + NH3<\/sub>\u00a0 \u00a0 \u2192\u00a0 \u00a0 C2<\/sub>H5<\/sub>NH2<\/sub> + HCl
        \n(C) Ethyl chloride\u00a0 \u00a0 \u00a0 (B) Ethyl amine<\/p>\n

        Question 53.
        \nA hydrocarbon C3<\/sub>H6<\/sub>(A) reacts with HBr to form compound (B). Compound (B) reacts with aqueous potassium hydroxide to give (C) of molecular formula C3<\/sub>H6<\/sub>O. What are the (A), (B) and (C). Explain the reactions.
        \nAnswer:
        \n\"Samacheer<\/p>\n

        Question 54.
        \nTwo isomers (A) and (B) have the same molecular formula C2<\/sub>H4<\/sub>Cl2<\/sub>. Compound (A) reacts with aqueous KOH gives compound (C) of molecular formula C2<\/sub>H4<\/sub>O. Compound (B) reacts with aqueous KOH gives compound (D) of molecular formula C2<\/sub>H6<\/sub>O2<\/sub>. Identify (A), (B), (C) and (D).
        \nAnswer:
        \n\"Samacheer<\/p>\n

        \"Samacheer<\/p>\n

        11th Chemistry Guide Haloalkanes and Haloarenes Additional Questions and Answers<\/h3>\n

        I. Choose the best answer:<\/span><\/p>\n

        Question 1.
        \nWhich of the following is an example of polyhalo compounds?
        \n(a) Vnyl iodide
        \n(b) Chiorobenzene
        \n(c) Allyl chloride
        \n(d) Chloroform
        \nAnswer:
        \n(d) Chloroform<\/p>\n

        Question 2.
        \n2\u00b0 halide among the following
        \na) isopropyl chloride
        \nb) isobutyl chloride
        \nc) n – propyl chloride
        \nd) n – butyl chloride
        \nAnswer:
        \na) isopropyl chloride<\/p>\n

        Question 3.
        \nHow many isomers are possible for the formula C4<\/sub>H9<\/sub>Cl?
        \n(a) 3
        \n(b) 2
        \n(c) 4
        \n(d) 5
        \nAnswer:
        \n(c) 4<\/p>\n

        Question 4.
        \nWhich of the following is gemdihalide?
        \na) CH3<\/sub>CHBrCH2<\/sub>Br
        \nb) CH3<\/sub>CHBr2<\/sub>
        \nc) CH3<\/sub>CHBrCH2<\/sub>CH2<\/sub>Br
        \nd) BrCH2<\/sub>CH2<\/sub>Br
        \nAnswer:
        \nb) CH3<\/sub>CHBr2<\/sub><\/p>\n

        Question 5.
        \nWhich of the following is called Lucas reagent?
        \n(a) Conc. H2<\/sub>SO4<\/sub> + Anhydrous CuSO4<\/sub>
        \n(b) Conc.HCl + Anhydrous ZnCl2<\/sub>
        \n(c) Dil.HCl + AlCl3<\/sub>
        \n(d) Conc.HCl + ConcHNO2<\/sub>
        \nAnswer:
        \n(b) Conc.HCl + Anhydrous ZnCl2<\/sub><\/p>\n

        \"Samacheer<\/p>\n

        Question 6.
        \nThe reagent used to get alkyl halide from alcohol
        \na) PCl5<\/sub>
        \nb) SOCl2<\/sub>
        \nc) Both a and b
        \nd) Cl2<\/sub>
        \nAnswer:
        \nc) Both a and b<\/p>\n

        Question 7.
        \nThe reactivity of alcohols with haloacid is –
        \n(a) 3\u00b0 > 2\u00b0 > 1\u00b0
        \n(b) 1\u00b0 > 2\u00b0 > 3\u00b0
        \n(c) 2\u00b0 > 3\u00b0 > 1\u00b0
        \n(d) 3\u00b0 > l\u00b0 > 2\u00b0
        \nAnswer:
        \n(a) 3\u00b0 > 2\u00b0> 1\u00b0<\/p>\n

        Question 8.
        \nIn the preparation of alkyl halide from alkane and halogen which of the following reaction involved
        \na) Electrophilic addition
        \nb) Nucleophilic addition
        \nc) Electrophilic substitution
        \nd) Nucleophilic substitution
        \nAnswer:
        \na) Electrophilic addition<\/p>\n

        Question 9.
        \nWhat is the name of the reaction in which bromoethane is converted to iodoethane by reacting with NaI in acetone?
        \n(a) Hunsdicker reaction
        \n(b) Dow\u2019s process
        \n(c) Finkelstein reaction
        \n(d) Swarts reaction
        \nAnswer:
        \n(c) Finkelstein reaction<\/p>\n

        Question 10.
        \nThe Grignard reagent is formed when alkyl halide reacts with which one of the following
        \na) Mg in alcohol
        \nb) Mg in acid
        \nc) Mg in dry ether
        \nd) MgO
        \nAnswer:
        \nc) Mg in dry ether<\/p>\n

        \"Samacheer<\/p>\n

        Question 11.
        \nWhich of the following pair functional groups represents ambident nucleophiles?
        \n(a)-SH-&-OH
        \n(b)-CN-&-NO2<\/sub>
        \n(c)-Br-&-Cl
        \n(d)-O-&-CHO
        \nAnswer:
        \n(b)-CN & NO2<\/sub><\/p>\n

        Question 12.
        \nAlkyl halide on reduction with Zn + HCl gives
        \na) alcohol
        \nb) alkene
        \nc) alkane
        \nd) ether
        \nAnswer:
        \nc) alkane<\/p>\n

        Question 13.
        \nWhich one of the following is used for producing pestic\u00ecdes?
        \n(a) CHI3<\/sub>
        \n(b) CHCl3<\/sub>
        \n(c) CCl3<\/sub> NO2<\/sub>
        \n(d) CCl4<\/sub>
        \nAnswer:
        \n(b) CHCl3<\/sub><\/p>\n

        Question 14.
        \nWhich of the reactions are most common in alkyl halides
        \na) Nucleophilic addition
        \nb) Electrophilic addition
        \nc) Nucleophilic substitution
        \nd) Electrophilic substitution
        \nAnswer:
        \nc) Nucleophilic substitution<\/p>\n

        Question 15.
        \nWhich one of the following reacts with CH3<\/sub>MgI followed by hydrolysis and gives isopropyl alcohol?
        \n(a) CH3<\/sub> COCH3<\/sub>
        \n(b) CH3<\/sub> CHO
        \n(c) HCHO
        \n(d) CNCl
        \nAnswer:
        \n(b) CH3<\/sub> CHO<\/p>\n

        \"Samacheer<\/p>\n

        Question 16.
        \nIn chloroethane the carbon-bearing halogen is bonded to ________.
        \na) three, primary
        \nb) two, secondary
        \nc) one, tertiary
        \nd) two, primary
        \nAnswer:
        \nd) two, primary<\/p>\n

        Question 17.
        \nWhich one of the following reacts with CH3 <\/sub>Mg I followed by acid hydrolysis to yield acetic acid?
        \n(a) CNCl
        \n(b) CH3<\/sub>COOC2<\/sub>H5<\/sub>
        \n(c) HCOOC2<\/sub>H5<\/sub>
        \n(d) CO2<\/sub>
        \nAnswer:
        \n(d) CO2<\/sub><\/p>\n

        Question 18.
        \nSN1<\/sup>reaction occurs through the intermediate formation of
        \na) carbocation
        \nb) carbanion
        \nc) free radicals
        \nd) transition
        \nAnswer:
        \na) carbocation<\/p>\n

        Question 19.
        \nWhich one of the following is used as a fiber-swelling agent in textile processing?
        \n(a) Chiorohenzene
        \n(b) Chloroform
        \n(c) Chlorai
        \n(d) Chloroethane
        \nAnswer:
        \n(a) Chiorobenzene<\/p>\n

        Question 20.
        \nThe most reactive nucleophile among the following is
        \na) CH3<\/sub>O–<\/sup>
        \nb) C6<\/sub>H5<\/sub>O–<\/sup>
        \nc) (CH3<\/sub>)2<\/sub>CHO–<\/sup>
        \nd) (CH3<\/sub>)3<\/sub>CO–<\/sup>
        \nAnswer:
        \na) CH3<\/sub>O–<\/sup><\/p>\n

        \"Samacheer<\/p>\n

        Question 21.
        \nWhich of the following reagent is used to distinguish gem-dihalides and vicinal dihalides?
        \n(a) Alcoholic KOH
        \n(b) Aqueous KOH
        \n(c) FeCl3 <\/sub>\/ Cl2<\/sub>
        \n(d) Ethanol
        \nAnswer:
        \n(b) Aqueous KOH<\/p>\n

        Question 22.
        \nIn SN2<\/sub> reactions the order of reactivity of the halides.
        \nCH3<\/sub>X, C2<\/sub>H5<\/sub>X , n – C3<\/sub>H7<\/sub>X, n- C4<\/sub>H9<\/sub>X is
        \na) CH3<\/sub>X > C2<\/sub>H5<\/sub>X > n – C3<\/sub>H7<\/sub>X > n – C4<\/sub>H9<\/sub>X
        \nb) C2<\/sub>H5<\/sub>X > n – C3<\/sub>H7<\/sub>X > n – C4<\/sub>H9<\/sub>X > CH3<\/sub>X
        \nc) C2<\/sub>H5<\/sub>X > n – C3<\/sub>H7<\/sub>X > n – C4<\/sub>H9<\/sub>X < CH3<\/sub>X
        \nd) n – C4<\/sub>H9<\/sub>X > n – C3<\/sub>H7<\/sub>X > C2<\/sub>H5<\/sub>X > CH3<\/sub>X
        \nAnswer:
        \na) CH3<\/sub>X > C2<\/sub>H5<\/sub>X > n – C3<\/sub>H7<\/sub>X > n – C4<\/sub>H9<\/sub>X<\/p>\n

        Question 23.
        \nWhich one of the following is used as a metal cleaning solvent?
        \n(a) Isopropylidene chloride
        \n(b) Methylene chloride
        \n(c) Chloroform
        \n(d) lodoform
        \nAnswer:
        \n(b) Methylene chloride<\/p>\n

        Question 24.
        \nIn Dow\u2019s process the starting raw material is
        \na) Phenol
        \nb) Chlorobenzene
        \nc) Aniline
        \nd) Diazobenzene
        \nAnswer:
        \nb) Chlorobenzene<\/p>\n

        Question 25.
        \nWhich one of the following is used to test primary amines?
        \n(a) Schiff\u2019s test
        \n(b) Carbylarnine test
        \n(c) Dye test
        \n(d) Silver mirror test
        \nAnswer:
        \n(b) Carbyianiine test<\/p>\n

        \"Samacheer<\/p>\n

        Question 26.
        \nChloro benzene is ________ reactive than benzene towards electrophilic substitution and directs incoming electrophile to the ______ position.
        \na) more, ortho & para
        \nb) less, ortho & para
        \nc) more, meta
        \nd) less, meta
        \nAnswer:
        \nb) less, ortho & para<\/p>\n

        Question 27.
        \nThe raw material for raschig; process is
        \na) chloro benzene
        \nb) phenol
        \nc) benzene
        \nd) anisol
        \nAnswer:
        \nc) benzene<\/p>\n

        Question 28.
        \nChloro benzene on treatment with sodium in dry ether gives diphenyl. The name of the reaction is
        \na) Fitting reaction
        \nb) Wurtz fittig reaction
        \nc) Wurtz reaction
        \nd) Sandmeyer reaction
        \nAnswer:
        \na) Fitting reaction<\/p>\n

        Question 29.
        \nWhich one of the following compounds does not undergo nucleophilic substitution reactions at all?
        \n(a) Ethyl bromide
        \n(b) Vinyl chloride
        \n(c) Benzyl chloride
        \n(d) isopropyl chloride
        \nAnswer:
        \n(b) Vinyl chloride<\/p>\n

        Question 30.
        \nThe raw materials for the commercial manufacture of DDT are
        \na) chloro benzene and chloroform
        \nb) chlorobenzene and chloromethane
        \nc) chloro benzene and chloral
        \nd) chloro benzene and iodoform
        \nAnswer:
        \nc) chloro benzene and chloral<\/p>\n

        \"Samacheer<\/p>\n

        Question 31.
        \nIodoform is used as
        \na) anesthetic
        \nb) antiseptic
        \nc) analgesic
        \nd) anti fibrin
        \nAnswer:
        \nb) antiseptic<\/p>\n

        Question 32.
        \nThe following is used in paint removing
        \na) CHCl3<\/sub>
        \nb) CH2<\/sub>Cl2<\/sub>
        \nc) CCl4<\/sub>
        \nd) CH3<\/sub>CI
        \nAnswer:
        \nb) CH2<\/sub>Cl2<\/sub><\/p>\n

        Question 33.
        \nIn fire extinguishers, following is used
        \na) CHCl3<\/sub>
        \nb) CS2<\/sub>
        \nc) CCl4<\/sub>
        \nd) CH2<\/sub>Cl2<\/sub>
        \nAnswer:
        \nc) CCl4<\/sub><\/p>\n

        Question 34.
        \nThe following is used for metal cleaning and finishing
        \na) CHCl3<\/sub>
        \nb) CHI3<\/sub>
        \nc) CH2<\/sub>Cl2<\/sub>
        \nd) C6<\/sub>H6<\/sub>
        \nAnswer:
        \nc) CH2<\/sub>Cl2<\/sub><\/p>\n

        Question 35.
        \nFirst chlorinated insecticide
        \na) DDT
        \nb) Gammaxene
        \nc) Iodoform
        \nd) Freon
        \nAnswer:
        \na) DDT<\/p>\n

        \"Samacheer<\/p>\n

        Question 36.
        \nThe following is used as anaesthetic
        \na) C2<\/sub>H4<\/sub>
        \nb) CHCl3<\/sub>
        \nc) CH2<\/sub>Cl2<\/sub>
        \nd) DDT
        \nAnswer:
        \nb) CHCl3<\/sub><\/p>\n

        Question 37.
        \nFreon – 12 is
        \na) CF3<\/sub>Cl
        \nb) CHCl2<\/sub>F
        \nc) CF2<\/sub>Cl2<\/sub>
        \nd) DDT
        \nAnswer:
        \nc) CF2<\/sub>Cl2<\/sub><\/p>\n

        Question 38.
        \nThe name of DDT
        \na) p, p’ – dichloro diphenyl trichloro ethane
        \nb) p, p’ – dichloro diphenyl trichloro ethene
        \nC) p, p’ – dichloro diphenyl tnchloro benzene
        \nd) p, p’ – tetra chloro ethane
        \nAnswer:
        \na) p, p’ – dichloro diphenyl trichloro ethane<\/p>\n

        Question 39.
        \nFreon R – 22 is
        \na) CHClF2<\/sub>
        \nb) CCl2<\/sub>F2<\/sub>
        \nc) CH3<\/sub>Cl
        \nd) CH2<\/sub>Cl2<\/sub>
        \nAnswer:
        \na) CHClF2<\/sub><\/p>\n

        Question 40.
        \nMolecular formula of DDT has
        \na) 5 Cl atoms
        \nb) 4 Cl atoms
        \nc) 3 Cl atoms
        \nd) 2 Cl atoms
        \nAnswer:
        \na) 5 Cl atoms<\/p>\n

        \"Samacheer<\/p>\n

        Question 41.
        \nWhat is DDT among the following
        \na) Green house gas
        \nb) A fertilizer
        \nc) Bio degradable pollutant
        \nd) Non – Bio degradable pollutant
        \nAnswer:
        \nd) Non – Bio degradable pollutant<\/p>\n

        Question 42.
        \nThe IUPAC name of (CH3<\/sub>)3<\/sub>CHCH2<\/sub>Br is
        \na) 1 – bromo – 2 – methyl propane
        \nb) 2 – bromo – 2 -methyl propane
        \nc) 1 – bromo – 1 – methyl propane
        \nd) 2 – bromo – 1 -methylpropane
        \nAnswer:
        \na) 1 – bromo – 2 – methyl propane<\/p>\n

        Question 43.
        \nIUPAC name of allyl chloride is
        \na) 1 – chloro ethane
        \nb) 3 – chloro- 1 – propyne
        \nc) 3 – chloro – 1 – propene
        \nd) 1 – chloro propane
        \nAnswer:
        \nc) 3 – chloro – 1 – propene<\/p>\n

        Question 44.
        \nThe number of structural isomers possible with the formula C4<\/sub>H9<\/sub>Cl are
        \na) 5
        \nb) 4
        \nc) 3
        \nd) 2
        \nAnswer:
        \nb) 4<\/p>\n

        Question 45.
        \nDensity is highest for
        \na) CH3<\/sub>Cl
        \nb) CH2<\/sub>Cl2<\/sub>
        \nc) CHCl3<\/sub>
        \nd) CCl4<\/sub>
        \nAnswer:
        \nd) CCl4<\/sub><\/p>\n

        \"Samacheer<\/p>\n

        Question 46.
        \nC2<\/sub>H5<\/sub>OH \"Samacheer X. In this reaction \u2018X\u2019 is
        \na) Ethanol
        \nb) Ethylene chloride
        \nc) ethylidene chloride
        \nd) ethyl chloride
        \nAnswer:
        \nd) ethyl chloride<\/p>\n

        Question 47.
        \nThionyl chloride is preferred in the preparation of chloro compound from alcohol since
        \na) Both the byproducts are gases and they escape out leaving product in pure state
        \nb) It is a chlorinating agent
        \nc) It is an oxidising agent
        \nd) All other reagents are unstable
        \nAnswer:
        \na) Both the byproducts are gases and they escape out leaving product in pure state<\/p>\n

        Question 48.
        \nThe only alkene which gives primary alkyl halides on hydro halogenation
        \na) C2<\/sub>H4<\/sub>
        \nb) C3<\/sub>H6<\/sub>
        \nc) C4<\/sub>H8<\/sub>
        \nd) C5<\/sub>H10<\/sub>
        \nAnswer:
        \na) C2<\/sub>H4<\/sub><\/p>\n

        Question 49.
        \n– OH cannot be replaced by – Cl if we use
        \na) PCl5<\/sub>
        \nb) PCl3<\/sub>
        \nc) S2<\/sub>Cl2<\/sub>
        \nd) SOCl2<\/sub>
        \nAnswer:
        \nc) S2<\/sub>Cl2<\/sub><\/p>\n

        Question 50.
        \nIn the hydrohalogenation of ethylene for adding HCl, the catalyst used is
        \na) Anhydrous AlCl3<\/sub>
        \nb) Conc. Sulphuric acid
        \nc) Dilute Sulphuric acid
        \nd) Anhydrous ZnCl2<\/sub>
        \nAnswer:
        \na) Anhydrous AlCl3<\/sub><\/p>\n

        \"Samacheer<\/p>\n

        Question 51.
        \nWhich one of the following has the lowest boiling point?
        \na) CH3<\/sub>Cl
        \nb) C2<\/sub>H5<\/sub>Cl
        \nc) C2<\/sub>H5<\/sub>Br
        \nd) C2<\/sub>H5<\/sub>I
        \nAnswer:
        \na) CH3<\/sub>Cl<\/p>\n

        Question 52.
        \nChloroethane is reacted with alcoholic potassium hydroxide. The product formed is
        \na) C2<\/sub>H6<\/sub>O
        \nb) C2<\/sub>H6<\/sub>
        \nc) C2<\/sub>H4<\/sub>
        \nd) C2<\/sub>H4<\/sub>O
        \nAnswer:
        \nc) C2<\/sub>H4<\/sub><\/p>\n

        Question 53.
        \nWhat is X in the following reaction? C2<\/sub>H5<\/sub>Cl + X \u2192 C2<\/sub>H5<\/sub>OH + KCl
        \na) KHCO3
        \nb) alc. KOH
        \nc) aq. KOH
        \nd) K2<\/sub>CO3<\/sub>
        \nAnswer:
        \nc) aq. KOH<\/p>\n

        Question 54.
        \nWhich of the following acids will give maximum yield of alkyl chloride in Hunsdiecker reaction
        \na) CH3<\/sub>CH2<\/sub>CH2<\/sub>COOH
        \nb) (CH3<\/sub>)2<\/sub>CHCOOH
        \nc) (CH3<\/sub>)3<\/sub>CCOOH
        \nd) C6<\/sub>H5<\/sub>CH (CH3<\/sub>)COOH
        \nAnswer:
        \na) CH3<\/sub>CH2<\/sub>CH2<\/sub>COOH<\/p>\n

        Question 55.
        \nIn the reaction sequence
        \nC2<\/sub>H5<\/sub>Cl + KCN X. What is the molecular formula of X is
        \na) C2<\/sub>H5<\/sub>CN
        \nb) C2<\/sub>H5<\/sub>NC
        \nc) C2<\/sub>H5<\/sub>OH
        \nd) C2<\/sub>H4<\/sub>O
        \nAnswer:
        \na) C2<\/sub>H5<\/sub>CN<\/p>\n

        \"Samacheer<\/p>\n

        Question 56.
        \nEthyl chloride on heating with silver cyanide forms a compound X. The functional isomer of X is
        \na) C2<\/sub>H5<\/sub>NC
        \nb) C2<\/sub>H5<\/sub>NCN
        \nc) H3<\/sub>C – NH – CH3<\/sub>
        \nd) C2<\/sub>H5<\/sub>NH2<\/sub>
        \nAnswer:
        \nb) C2<\/sub>H5<\/sub>NCN<\/p>\n

        Question 57.
        \nWith Zn – Cu couple and C2<\/sub>H5<\/sub>OH, ethyl Iodide reacts to give
        \na) ethers
        \nb) diethyl ether
        \nc) Iodoform
        \nd) Ethane
        \nAnswer:
        \nd) Ethane<\/p>\n

        Question 58.
        \nEthyl bromide on boiling with alcoholic solutions of sodium hydroxide forms
        \na) Ethane
        \nb) ethylene
        \nc) ethyl alcohol
        \nd) all of these
        \nAnswer:
        \nb) ethylene<\/p>\n

        Question 59.
        \nFollowing major compound is formed when ethyl chloride reacts with silver nitrite
        \na) Nitroethane
        \nb) Ethyl nitrite
        \nc) Ethylene
        \nd) Acetaldehyde
        \nAnswer:
        \nb) Ethyl nitrite<\/p>\n

        Question 60.
        \nWhich of the following represents Williamson\u2019s synthesis?
        \na) CH3<\/sub>COOH + PCl3<\/sub> \u2192
        \nb) CH3<\/sub> – CH2<\/sub> – Cl + CH3<\/sub>COOH \u2192
        \nc) CH3 <\/sub>– CH2 <\/sub>– ONa + CH3<\/sub> – CH2<\/sub> – Cl \u2192
        \nd) CH3<\/sub> – CH2<\/sub> – OH + Na \u2192
        \nAnswer:
        \nc) CH3 <\/sub>– CH2 <\/sub>– ONa + CH3<\/sub> – CH2<\/sub> – Cl \u2192<\/p>\n

        \"Samacheer<\/p>\n

        Question 61.
        \nThe reaction of an alkyl halide with benzene in presence of anhydrous A1Cl3<\/sub> gives alkyl benzene the reaction is known as
        \na) Friedel – craft\u2019s reaction
        \nb) Carbylamine reaction
        \nc) Gattermann reaction
        \nd) Wurtz reaction
        \nAnswer:
        \na) Friedel – craft\u2019s reaction<\/p>\n

        Question 62.
        \nA Grignard\u2019s reagent reacts with water to give
        \na) ether
        \nb) alkanes
        \nc) amine
        \nd) Alcohol
        \nAnswer:
        \nb) alkanes<\/p>\n

        Question 63.
        \nC2<\/sub>H5<\/sub>Cl + Mg \u2192 C2<\/sub>H5<\/sub> MgCl in this reaction the solvent is
        \na) C2<\/sub>H5<\/sub>OH
        \nb) Water
        \nc) Dry ether
        \nd) Acetone
        \nAnswer:
        \nc) Dry ether<\/p>\n

        Question 64.
        \nFor a nucleophilic substitution reaction the rate was found in the order RI > RBr > RCl > RF then the reaction could be
        \na) SN1<\/sup><\/sub> only
        \nb) SN2<\/sup><\/sub> only
        \nc) Either SN1<\/sup><\/sub> or SN2<\/sup><\/sub>
        \nd) Neither SN1<\/sup><\/sub> or SN2<\/sup><\/sub>
        \nAnswer:
        \nc) Either SN1<\/sup><\/sub> or SN2<\/sup><\/sub><\/p>\n

        Question 65.
        \nSN2<\/sup><\/sub> reaction leads to
        \na) inversion of configuration
        \nb) retention of configuration
        \nc) partial racemisation
        \nd) no racemisation
        \nAnswer:
        \na) inversion of configuration<\/p>\n

        \"Samacheer<\/p>\n

        Question 66.
        \nWhich of the following alkyl halide is hydrolysed by SN1<\/sup><\/sub> mechanism
        \na) CH3<\/sub>Cl
        \nb) CH3<\/sub> – CH2<\/sub> – Cl
        \nc) CH3<\/sub> – CH2<\/sub> – CH2<\/sub> – Cl
        \nd) (CH3<\/sub>)3<\/sub>CCl
        \nAnswer:
        \nd) (CH3<\/sub>)3<\/sub>CCl<\/p>\n

        Question 67.
        \nSN1<\/sup><\/sub> reaction is favoured by
        \na) non – polar solvents
        \nb) Bulky group on the carbon atom attached to the halogen atom
        \nc) Small groups on the carbon atom attached to halogen atom
        \nd) All of the above
        \nAnswer:
        \nb) Bulky group on the carbon atom attached to the halogen atom<\/p>\n

        Question 68.
        \nWhich of the following is not stereospecific
        \na) SN1<\/sup><\/sub>
        \nb) SN2<\/sup><\/sub>
        \nc) E2<\/sub>
        \nd) Addition of Br2<\/sub> to ethylene in CCl4<\/sub>
        \nAnswer:
        \na) SN1<\/sup><\/sub><\/p>\n

        Question 69.
        \nWhich of the following factors does not favour SN1<\/sup><\/sub> mechanism
        \na) Strong base
        \nb) Polar solvent
        \nc) Low. conc. of nucleophile
        \nd) 3\u00b0 halide
        \nAnswer:
        \nc) Low. conc. of nucleophile<\/p>\n

        Question 70.
        \nThe order of reactivity of various alkyl halides toward SN1 reaction is
        \na) 3\u00b0 > 2\u00b0 > 1\u00b0
        \nb) 1\u00b0 > 2\u00b0 > 3\u00b0
        \nc) 3\u00b0 = 2\u00b0 = 1\u00b0
        \nd) 1\u00b0 > 3\u00b0 > 2\u00b0
        \nAnswer:
        \na) 3\u00b0 > 2\u00b0 > 1\u00b0<\/p>\n

        \"Samacheer<\/p>\n

        Question 71.
        \nIn aryl halides carbon atom holding halogen is
        \na) sp2<\/sup> hybridised
        \nb) sp hybridised
        \nc) sp3<\/sup> hybndised
        \nd) sp3<\/sup>d hybridised
        \nAnswer:
        \na) sp2<\/sup> hybridised<\/p>\n

        Question 72.
        \nChloro benzene can be prepared by reacting benzene diazonlum chloride with
        \na) HCl
        \nb) Cu2<\/sub>Cl2<\/sub> \/ HCl
        \nc) Cl2<\/sub> \/ AlCl3<\/sub>
        \nd) HNO2<\/sub>
        \nAnswer:
        \nb) Cu2<\/sub>Cl2<\/sub> \/ HCl<\/p>\n

        Question 73.
        \n\"Samacheer + Cl2<\/sub> \"Samacheer X, X is
        \na) Chlorobenzene
        \nb) m – dichloro benzene
        \nc) benzene hexachioride
        \nd) p – dichlorobenzene
        \nAnswer:
        \na) Chlorobenzene<\/p>\n

        Question 74.
        \nThe following is an example of Sandmeyer reaction
        \na) C6<\/sub>H5<\/sub>N2<\/sub>+<\/sup> Cl–<\/sup> \"Samacheer C6<\/sub>H5<\/sub>Cl
        \nb) C6<\/sub>H5<\/sub>N2<\/sub>+<\/sup> Cl–<\/sup> \"Samacheer C6<\/sub>H5<\/sub>OH
        \nc) C6<\/sub>H5<\/sub>N2<\/sub>+<\/sup> Cl–<\/sup> \"Samacheer C6<\/sub>H5<\/sub>F
        \nd) C6<\/sub>H5<\/sub>N2<\/sub>+<\/sup> Cl–<\/sup> \"Samacheer C6<\/sub>H5<\/sub>Cl
        \nAnswer:
        \na) C6<\/sub>H5<\/sub>N2<\/sub>+<\/sup> Cl–<\/sup> \"Samacheer C6<\/sub>H5<\/sub>Cl<\/p>\n

        Question 75.
        \nChlorobenzene on reaction with CH3<\/sub>Cl in presence of AlCl3<\/sub> gives
        \na) toulene
        \nb) m – chloro toulene
        \nc) only o – chloro toulene
        \nd) mixture of o – and p – chlorotoulene
        \nAnswer:
        \nd) mixture of o – and p – chlorotoulene<\/p>\n

        \"Samacheer<\/p>\n

        Question 76.
        \n2C6<\/sub>H5<\/sub>Cl + 2Na \u2192 X, X is
        \na) toulene
        \nb) biphenyl
        \nC) phenyl ethane
        \nd) 1 – chloro – 2 – phenyl ethane
        \nAnswer:
        \nb) biphenyl<\/p>\n

        Question 77.
        \nChlorobenzene on fusing with solid NaOH gives
        \na) benzene
        \nb) benzoic acid
        \nc) phenol
        \nd) benzene chloride
        \nAnswer:
        \nc) phenol<\/p>\n

        Question 78.
        \nChlorobenzene on nitration gives major product of
        \na) 1 – chloro – 4 – nitro benzene
        \nb) 1 – chloro – 3 – nitro benzene
        \nc) 1, 4 – dinitro benzene
        \nd) 2, 4, 6 – tri nitro benzene
        \nAnswer:
        \na) 1 – chloro – 4 – nitro benzene<\/p>\n

        Question 79.
        \nThe reaction C6<\/sub>H5<\/sub>I + 2 Na + CH3<\/sub>I \u2192 C6<\/sub>H5<\/sub>CH3<\/sub> + 2 NaI is
        \na) Wurtz reaction
        \nb) Fittig reaction
        \nc) Wurtz-Fittig reaction
        \nd) Sandmeyer reaction
        \nAnswer:
        \nc) Wurtz-Fittig reaction<\/p>\n

        Question 80.
        \nR – Cl + Nal \"Samacheer R – I + NaCl. This reaction is
        \na) Wurtz reaction
        \nb) Fittig reaction
        \nc) Finkelstein reaction
        \nd) Frankland reaction
        \nAnswer:
        \nc) Finkelstein reaction<\/p>\n

        \"Samacheer<\/p>\n

        Question 81.
        \nC2<\/sub>H5<\/sub>OH + SOCl2<\/sub> \"Samacheer x + y + z. In this reaction x, y and z respectively are
        \na) C2<\/sub>H4<\/sub>Cl2<\/sub>, SO2<\/sub>, HCl
        \nb) C2<\/sub>H5<\/sub>Cl, SO2<\/sub>, HCl
        \nc) C2<\/sub>H5<\/sub>Cl, SOCl, HCl
        \nd) C2<\/sub>H4<\/sub>, SO2<\/sub>, Cl2<\/sub>
        \nAnswer:
        \nb) C2<\/sub>H5<\/sub>Cl, SO2<\/sub>, HCl’<\/p>\n

        Question 82.
        \nC2<\/sub>H5<\/sub>Cl + AgOH \u2192 A + AgCl.
        \nA + CH3<\/sub>COCl \u2192 C + HCl. “C” is
        \na) Ethyl acetate
        \nb) Methyl acetate
        \nc) butanone – 2
        \nd) propanone
        \nAnswer:
        \na) Ethyl acetate<\/p>\n

        Question 83.
        \nThe compound (B) in the below reaction is:
        \nC2<\/sub>H5<\/sub>Cl \"Samacheer A \"Samacheer B
        \na) ethylene chloride
        \nb) acetic acid
        \nc) propionic acid
        \nd) ethyl cyanide
        \nAnswer:
        \nc) propionic acid<\/p>\n

        Question 84.
        \nChloro ethane reacts with X to form diethyl ether. What is X?
        \na) NaOH
        \nb) H2<\/sub>SO4<\/sub>
        \nc) C2<\/sub>H5<\/sub>ONa
        \nd) Na2<\/sub>S2<\/sub>O3<\/sub>
        \nAnswer:
        \nc) C2<\/sub>H5<\/sub>ONa<\/p>\n

        Question 85.
        \n1 – chlorobutane on reaction with alcoholic potash gives
        \na) 1 – butene
        \nb) 1 – butanol
        \nc) 1 – butyne
        \nd) 2 – butanol
        \nAnswer:
        \na) 1 – butene<\/p>\n

        \"Samacheer<\/p>\n

        Question 86.
        \nPropane nitrile may be prepared by heating
        \na) Propyl alcohol with KCN
        \nb) ethyl chloride with KCN
        \nc) Propyl chloride with KCN
        \nd) ethyl chloride with KCN
        \nAnswer:
        \nd) ethyl chloride with KCN<\/p>\n

        Question 87.
        \nCH3<\/sub>CH = CH2<\/sub> \"Samacheer A \"Samacheer B, B is
        \na) propanol – 2
        \nb) propanal – 1
        \nc) propanol – 1
        \nd) propanal – 2
        \nAnswer:
        \nc) propanol – 1<\/p>\n

        Question 88.
        \n\"Samacheer Y is
        \n\"Samacheer
        \nAnswer:
        \nc) \"Samacheer<\/p>\n

        Question 89.
        \nThe correct order of increasing boiling points is
        \na) 1 – chloropropane < isopropylchloride < 1 – chlorobutane
        \nb) isopropylchloride < 1 – chloropropane < 1 – chlorobutane
        \nc) 1 – chlorobutane < isopropylchloride < 1 – chloropropane
        \nd) 1 – chlorobutane < 1 – chloropropane < isopropylchloride
        \nAnswer:
        \nb) isopropylchloride < 1 – chloropropane < 1 – chlorobutane<\/p>\n

        Question 90.
        \nThe correct order of decreasing SN2<\/sup><\/sub> reactivity
        \na) RCH2<\/sub>X > R2<\/sub>CHX > R3<\/sub>CX
        \nb) RCH2<\/sub>X > R3<\/sub>CX > R2<\/sub>CHX
        \nc) R2<\/sub>CHX > R3<\/sub>CX > RCH2<\/sub>X
        \nd) R3<\/sub>CX > R2<\/sub>CHX > RCH2<\/sub>X
        \nAnswer:
        \na) RCH2<\/sub>X > R2<\/sub>CHX > R3<\/sub>CX<\/p>\n

        \"Samacheer<\/p>\n

        II. Very short question and answer (2 Marks):<\/span><\/p>\n

        Question 1.
        \nWhat are haloalkanes? Give example.
        \nAnswer:
        \nMono halogen derivatives of alkanes are called haloalkanes. Haloalkanes are represented by general formula R – X, Where, R is an alkyl group (Cn<\/sub>H2n + 1<\/sub>) – and X is a halogen atom (X = F, Cl, Br or I). Haloalkanes are further classified into primary, secondary, tertiary haloalkane on the basis of type of carbon atom to which the halogen is attached.
        \nExample:
        \n\"Samacheer<\/p>\n

        Question 2.
        \nHow will you convert methane into tetra chloro methane?
        \nAnswer:
        \nChlorination of methane gives different products which have differences in the boiling points. Hence, these can be separated by fractional distillation.
        \n\"Samacheer<\/p>\n

        Question 3.
        \nWhat is Finkelstein’s reaction?
        \nAnswer:
        \nChloro or bromoalkane on heating with a concentrated solution of sodium iodide in dry acetone gives iodo alkanes. This reaction is called as Finkelstein reaction.
        \nCH3<\/sub>CH2<\/sub>Br + NaI \"Samacheer CH3<\/sub>CH2<\/sub>I + NaI
        \nBromo ethane Iodoethane<\/p>\n

        Question 4.
        \nWhat is Swartz reaction?
        \nAnswer:
        \nChloro or bromo alkanes on heating with metallic fluorides like AgF or SbF3<\/sub> gives fluoro alkanes. This reaction is called Swarts reaction.
        \nCH3<\/sub>CH2<\/sub>Br + AgF \"Samacheer CH3<\/sub>CH2<\/sub>F + AgBr
        \nBromo ethane Fluoro ethane<\/p>\n

        Question 5.
        \nWhat is Hunsdiecker’s reaction?
        \nAnswer:
        \nSilver salts of fatty acids when refluxed with bromine in CCl4<\/sub> gives bromo alkane.
        \nCH3<\/sub>CH2<\/sub>COOAg + Br2<\/sub> \"Samacheer CH3<\/sub>CH2<\/sub>Br + CO2<\/sub> + AgBr
        \nSilver propionate Bromo ethane<\/p>\n

        \"Samacheer<\/p>\n

        Question 6.
        \nHow is ehtyl magnesium bromide prepared from ethyl bromide?
        \nAnswer:
        \nWhen a solution of ethyl bromide in ether is treated with magnesium, we get ethyl magnesium bromide.
        \nCH3<\/sub> – CH2<\/sub> – Br + Mg \"Samacheer CH3<\/sub>CH2<\/sub>MgBr
        \nEthyl bromide Ethyl magnesium bromide<\/p>\n

        Question 7.
        \nHow will you convert ethyl bromide into ethyl lithium?
        \nAnswer:
        \nEthyl bromide reacts with active metals like sodium, lead etc in the presence of dry ether to form ethyl lithium.
        \nCH3<\/sub> CH2<\/sub> Br + 2Li \"Samacheer CH3<\/sub> CH2<\/sub>Li + LiBr
        \nEthyl bromide Ethyl Lithium<\/p>\n

        Question 8.
        \nHow is TEL prepared from ethyl bromide?
        \nAnswer:
        \nWhen ethyl bromide reacts with Na \/ Pb alloy to give TEL.
        \n4CH3<\/sub> CH2<\/sub> Br + 4Na\/Pb \u2192 (CH3<\/sub>CH2<\/sub>)4<\/sub>Pb + 4NaBr + 3Pb
        \nEthyl bromide Sodium-lead alloy Tetraethyl lead (TEL)<\/p>\n

        Question 9.
        \nHaloalkanes have higher boiling point and melting point than the parent alkane. Justify this statement.
        \nAnswer:
        \nHaloalkanes have higher boiling point than the parent alkane having the same number of carbon atoms because the intermolecular forces of attraction and dipole-dipole interactions are comparatively stronger in haloalkanes.<\/p>\n

        Question 10.
        \nHow is methane prepared from Grignard reagent?
        \nAnswer:
        \nCompounds like water, alcohols and amines which contain active hydrogen atom react with Grignard reagents to form alkanes.
        \nCH3<\/sub>MgI + HO – H \u2192 CH4<\/sub> + Mg I (OH)<\/p>\n

        CH3<\/sub>MgI + C2<\/sub>H5<\/sub>OH\u00a0 \u00a0 \u00a0 \u00a0 \u00a0\"Samacheer CH4<\/sub> + MgI (OC2<\/sub>H5<\/sub>)
        \nEthyl alcohol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Methane<\/p>\n

        \"Samacheer<\/p>\n

        Question 11.
        \nWhat are Haloarenes? Give a suitable example.
        \nAnswer:
        \nHaloarenes are the compounds in which the halogen is directly attached to the benzene ring.
        \nExample:
        \n\"Samacheer<\/p>\n

        Question 12.
        \nHow is chloro benzene prepared from benzene by direct halogenation?
        \nAnswer:
        \nChloro benzene is prepared by the direct chlorination of benzene in the presence of lewis acid catalyst like FeCl3<\/sub>.
        \n\"Samacheer<\/p>\n

        Question 13.
        \nWrite a note on Sand Meyer reaction.
        \nAnswer:
        \nWhen aqueous solution of benzene diazonium chloride is warmed with Cu2<\/sub>Cl in HCl gives chioro benzene.
        \n\"Samacheer<\/p>\n

        Question 14.
        \nHow is Iodo benzene prepared from benzene diazonium chloride?
        \nAnswer:
        \nIodo benzene is prepared by warming benzene diazonium chloride with an aqueous KI solution.
        \nC6<\/sub>H5<\/sub>N2<\/sub>Cl + Kl\u00a0 \u00a0 \"Samacheer\u00a0 \u00a0 \u00a0 C6<\/sub>H5<\/sub>I + N2<\/sub> + KCl
        \nBenzene dizonium chloride\u00a0 \u00a0 \u00a0 \u00a0 Iodo benzene<\/p>\n

        Question 15.
        \nWhat happens when ethylidene dichloride is treated with Zinc dust in methanol?
        \nAnswer:
        \nGem dihalides and vic – dihalides on treatment with zinc dust in methanol give alkenes.
        \nCH3<\/sub> – CHCl2<\/sub> + Zn \"Samacheer CH2<\/sub> = CH2<\/sub> + ZnCl2<\/sub>
        \nEthylidene dichloride\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethylene<\/p>\n

        \"Samacheer<\/p>\n

        Question 16.
        \nHow will you convert chloroform into methylene chloride?
        \nAnswer:
        \na) Reduction of chloroform in the presence of Zn + HCl gives methylene chloride.
        \nCHCl3<\/sub> (chloroform) \"Samacheer CH2<\/sub>Cl (Methylene chloride) + HCl
        \nb) Reduction of chloroform using H2\/Ni
        \nCHCl3<\/sub> (chloroform) \"Samacheer CH2<\/sub>Cl2<\/sub> (Methylene chloride) + HCl<\/p>\n

        Question 17.
        \nWrite the chlorination reaction of methane.
        \nAnswer:
        \nChlorination of methane gives methylene chloride
        \nCH4<\/sub> \"Samacheer CH3<\/sub>Cl \"Samacheer CH2<\/sub>Cl2<\/sub>
        \nMethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Methylene chloride<\/p>\n

        Question 18.
        \nHow is chloroform prepared from carbon tetrachloride?
        \nAnswer:
        \nCarbon tetrachloride is reduced by iron powder in dilute HCl medium to form chloroform
        \nCCl4<\/sub> (carbon tetrachloride) + 2[H] \"Samacheer CHCl3<\/sub> (chloroform) + HCl<\/p>\n

        \"Samacheer<\/p>\n

        III. Short question and answers (3 Marks):<\/span><\/p>\n

        Question 1.
        \nwrite the IUPAC name of the following.
        \ni) \"Samacheer<\/p>\n

        ii) \"Samacheer<\/p>\n

        iii) \"Samacheer
        \nAnswer:
        \ni) \"Samacheer<\/p>\n

        ii) \"Samacheer<\/p>\n

        iii) \"Samacheer<\/p>\n

        Question 2.
        \nWrite the structure of the following compounds.
        \ni) 1 – Bromo – 4 – ethyl cyclohexane
        \nii) 1, 4 – Dichlorobut – 2 – ene
        \niii) 2 – chloro – 3 – methyl pentane
        \nAnswer:
        \ni) 1 -Bromo – 4 – ethyl cyclohexane:
        \n\"Samacheer<\/p>\n

        ii) 1, 4 – Dichlorobut – 2 – ene
        \n– Cl – CH2<\/sub> – CH = CH – CH2<\/sub> – Cl<\/p>\n

        iii) 2 – chloro – 3 – methyl pentane
        \n\"Samacheer<\/p>\n

        Question 3.
        \nWrite any three methods of preparation of chloro ethane from ethanol.
        \nAnswer:
        \na) Reaction with hydrogen halide:
        \nEthanol is heated with HCl in presence of anhydrous ZnCl2<\/sub> to give ethyl chloride.
        \nCH3<\/sub>CH2<\/sub>OH + HCl \"Samacheer CH3<\/sub>CH2<\/sub>Cl + H2<\/sub>O
        \nEthanol Chloroethane<\/p>\n

        b) Reaction with phosphorous halides:
        \nEthanol reacts with PCl5<\/sub> or PCl3<\/sub> it gives ethyl chloride.
        \nCH3<\/sub>CH2<\/sub>OH + PCl5<\/sub> \u2192 CH3<\/sub>CH2<\/sub>Cl + POCl3<\/sub> + HCl
        \nEthanol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Chloro ethane<\/p>\n

        3 CH3<\/sub>CH2<\/sub>OH + PCl3<\/sub> \u2192 3CH3<\/sub>CH2<\/sub>Cl + H 3<\/sub>PO3<\/sub>
        \nEthanol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Chloro ethane<\/p>\n

        C) Reaction with thionyl chloride (Sulphonyl chloride):
        \nWhen ethanol reacts with SOCl2<\/sub> in presence of pyridine, it gives chloro ethane.
        \nCH3<\/sub>CH2<\/sub>OH + SOCl2<\/sub> \"Samacheer CH3<\/sub>CH2<\/sub>Cl + SO2<\/sub> + HCl
        \nEthanol\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Chloro ethane<\/p>\n

        Question 4.
        \nWhat happens when haloalkane reacts with aqueous alkali or most silver oxide?
        \nAnswer:
        \nEthyl bromide reacts with aqueous solution of KOH or moist silver oxide (Ag2<\/sub>O\/H2<\/sub>O) to form ethanol.
        \nCH3<\/sub> – CH2<\/sub> – Br + KOH (aq) \"Samacheer CH3<\/sub>CH2<\/sub> – OH + KBr
        \nBromoethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethyl alcohol<\/p>\n

        CH3<\/sub> – CH2<\/sub> – Br\u00a0 \u00a0+\u00a0 \u00a0AgOH(aq)\u00a0 \u00a0\"Samacheer CH3<\/sub>CH2<\/sub> – OH + AgBr
        \nBromoethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0Moist silver oxide\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Ethanol<\/p>\n

        Question 5.
        \nExplain the ammonolysis reaction of bromo ethane.
        \nAnswer:
        \nEthyl bromide reacts with alcoholic ammonia solution to form ethylamine.
        \nCH3<\/sub> – CH2<\/sub> – Br + H – NH2<\/sub> \u2192 CH3<\/sub> CH2<\/sub> – NH2<\/sub> + HBr
        \nBromo ethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Ethyl amine<\/p>\n

        \"Samacheer
        \nHowever, with excess of ethyl bromide, secondary and tertiary amines along with quaternary ammonium salts are obtained.<\/p>\n

        \"Samacheer<\/p>\n

        Question 6.
        \nExplain the hydrolysis of 2-bromobutane with aqueous KOB.
        \nAnswer:<\/p>\n

          \n
        • 2-bromobutane is optically active and it undergoes SN1<\/sup><\/sub> reaction with aqueous KOH.<\/li>\n
        • The product obtained will be an optically inactive racemic mixture.<\/li>\n
        • As nucleophilic reagent OH–<\/sup> ion can attack the carbocation from both sides to form equal proportions of dextro and levorotatory optically active isomers, it results in the formation of an optically inactive racemic mixture.<\/li>\n<\/ul>\n

          Question 7.
          \nHow are the following compounds prepared from bromo ethane?
          \ni) Ethane thiol
          \n(ii) Diethyl ether
          \nAnswer:
          \ni) Ethane thiol:
          \nEthyl bromide reacts with sodium or potassium hydrogen sulphide to form thio alcohols.
          \nCH3<\/sub>CH2<\/sub>Br \"Samacheer CH3<\/sub>CH2<\/sub>SH + NaBr
          \nBromo ethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethane thiol<\/p>\n

          ii) Diethyl ether:
          \nEthyl bromide, when boiled with sodium alkoxide gives diethyl ether. This method can be used to prepare mixed (unsymmetrical) ethers also.
          \nCH3<\/sub> – CH2<\/sub>Br +\u00a0 \u00a0 \u00a0 NaOCH2<\/sub>CH3\u00a0 \u00a0 \u00a0<\/sub> \"Samacheer\u00a0 \u00a0 CH3<\/sub>CH2<\/sub> – O – CH2<\/sub>CH3<\/sub> + NaBr
          \nBromo ethane\u00a0 \u00a0 \u00a0 \u00a0 Sodium ethoxide\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0diethyl ether<\/p>\n

          Question 8.
          \nHow is ethane prepared from the following compounds?
          \ni) Bromo ethane ii) Iodo ethane
          \nAnswer:
          \ni) From bromo ethane:
          \nEthyl bromide is reduced to ethane by treating with H2<\/sub> in the presence of metal catalyst like nickel, palladium etc or with hydroiodic acid in the presence of red phosphrous.
          \nNi(or)Pd
          \nCH3<\/sub>CH2<\/sub>Br + H2<\/sub> \"Samacheer CH3<\/sub> – CH3<\/sub> + HBr
          \nBromo ethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Ethane<\/p>\n

          ii) From iodo ethane:
          \nIodo ethane is reduced with H2<\/sub> in presence of Red P it gives ethane.
          \nCH3<\/sub>CH2<\/sub>I + HI \"Samacheer CH3<\/sub> – CH3<\/sub> + I2<\/sub>
          \nIodo ethane\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Ethane<\/p>\n

          Question 9.
          \nWhat are the uses of carbon tetrachioride?
          \nAnswer:<\/p>\n

            \n
          • Carbon tetrachioride in used as a dry cleaning agent.<\/li>\n
          • It is used as a solvent for oils, fats and waxes.<\/li>\n
          • As the vapours of CCl4<\/sub> is non-combustible, it is used under the name pyrene for extinguishing the fire caused by oil (or) petrol.<\/li>\n<\/ul>\n

            Question 10.
            \nWrite the uses of Grignard reagents.
            \nAnswer:<\/p>\n

              \n
            1. Grignard reagents are synthetically very useful compounds. These reagents are converted to various organic compounds like alcohols, carboxylic acids, aldehydes and ketones.<\/li>\n
            2. The alkyl group being electron rich acts as a carbanion or a nucleophile.<\/li>\n
            3. They would attack polarized molecules at a point of low electron density. The following reactions illustrate the synthetic uses of the Grignard reagent.<\/li>\n<\/ol>\n

              \"Samacheer<\/p>\n

              Question 11.
              \nWhat is Balz – Schiemann reaction?
              \nAnswer:
              \nFluoro benzene is prepared by treating benzene diazonium chloride with fluoro boric acid. This reaction produces diazonium fluoroborate which on heating produces fluorobenzene. This reaction is called Balz – Schiemann reaction.
              \nC6<\/sub>H5<\/sub>N2<\/sub>Cl + HBF4<\/sub> \"Samacheer C6<\/sub>H5<\/sub>N2<\/sub> + BF4<\/sub>–<\/sup> \"Samacheer C6<\/sub>H5<\/sub> F + BF3<\/sub> + N2<\/sub>
              \nBenzene diazonium chloride\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Fluorobenzene<\/p>\n

              Question 12.
              \nWhat are the uses of chlorobenzene?
              \nAnswer:<\/p>\n

                \n
              • Chlorobenzene is used in the manufacture of pesticides like DDT.<\/li>\n
              • It is used as high boiling solvent in organic synthesis.<\/li>\n
              • It is used as a fibre – swelling agent in textile processing.<\/li>\n<\/ul>\n

                Question 13.
                \nHow is ethylidene dichloride prepared from
                \n(i) Acetaldehyde
                \n(ii) Acetylene
                \nAnswer:
                \ni) Treating acetaldehyde with PCl5<\/sub>:
                \nCH3<\/sub>CHO (Acetaldehyde) + PCl5<\/sub> \u2192 CH3<\/sub>CHCl2 <\/sub>(Ethylidene dichloride) + POCl<\/p>\n

                ii) Adding hydrogen chloride to acetylene
                \n\"Samacheer<\/p>\n

                Question 14.
                \nHow is ethylene dichloride prepared from
                \n(i) Chloride?
                \n(ii) PCl5<\/sub>?
                \nAnswer:
                \ni) Addition of chlorine to ethylene
                \n\"Samacheer<\/p>\n

                ii) Action of PCl5<\/sub> (or HCl) on ethylene glycol<\/p>\n

                \"Samacheer<\/p>\n

                Question 15.
                \nWhat happens when the following compounds are treated with alcoholic KOH?
                \ni) Ethylidene dichloride
                \nii) Ethylene dichloride
                \nAnswer:
                \ni) Ethylidene dichloride:
                \n\"Samacheer<\/p>\n

                ii) Ethylene dichloride:
                \n\"Samacheer<\/p>\n

                \"Samacheer<\/p>\n

                Question 16.
                \nWhat are the uses of methylene chloride?
                \nAnswer:
                \nMethylene chloride is used as:<\/p>\n

                  \n
                • Aerosol spray propellant.<\/li>\n
                • Solvent in paint remover.<\/li>\n
                • Process solvent in the manufacture of drugs.<\/li>\n
                • A metal cleaning agent.<\/li>\n<\/ul>\n

                  Question 17.
                  \nHow are the following compounds prepared from chlorobenzene?
                  \ni) Benzene
                  \nii) Phenyl magnesium chloride
                  \nAnswer:
                  \ni) C6<\/sub>H6<\/sub> (Benzene):
                  \nChlorbenzene undergoes reduction with Ni – Al alloy in the presence of NaOH gives benzene.
                  \nC6<\/sub>H5<\/sub>Cl + 2(H) \"Samacheer C6<\/sub>H6<\/sub> + HCl
                  \nChloro benzene\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Benzeneide<\/p>\n

                  ii) Phenyl Magnesium chloride:
                  \nChloro benzene reacts with magnesium to form phenyl magnesium chloride in tetra hydrofuran (THF).
                  \nC6<\/sub>H5<\/sub>Cl (Chloro benzene) + Mg \"Samacheer C6<\/sub>H5<\/sub>MgCl (Phenyl magnesium chloride)<\/p>\n

                  \"Samacheer<\/p>\n

                  IV. Long question and answers (5 Marks):<\/span><\/p>\n

                  Question 1.
                  \nExplain the SN2<\/sup><\/sub> mechanism of haloalkanes with a suitable example.
                  \nAnswer:
                  \nS2 stands for bimolecular nucleophilic substitution
                  \n\u201cS\u201d stands for substitution
                  \n\u201cN\u201d stands for nucleophilic
                  \n\u201c2\u201d stands for bimolecular (two molecules are involved in the rate-determining step)
                  \nThe rate of SN2<\/sup><\/sub> reaction depends upon the concentration of both alkyl halide and the nucleophile.
                  \nRate of reaction = k2<\/sub> [alkyihalide] [nucleophile]
                  \nThis SN2<\/sup><\/sub> reaction follows second-order kinetics and occurs in one step.<\/p>\n

                  This reaction involves the formation of a transition state in which both the reactant molecules are partially bonded to each other. The attack of nucleophile occurs from the backside and the halide ion leaves from the front side. The carbon at which substitution ocurs ha inverted configuration during the course of reaction just as an umbrella has tendency to invert in a wind storm. This inversion of configuration is called Walden inversion; after paul Walden who first discovered the inversion of configuration of a compound in SN2<\/sup><\/sub> reaction.<\/p>\n

                  We understand SN2<\/sup><\/sub> reaction mechanism by taking an example of reaction between chloromethane and aqueous KOH. SN2<\/sup><\/sub> reaction of an optically active haloalkane is always accompanied by inversion of configuration at the asymmetric centre.<\/p>\n

                  \"Samacheer<\/p>\n

                   <\/p>\n

                  \"Samacheer<\/p>\n

                  Question 2.
                  \nExplain the SN1<\/sup><\/sub> mechanism of haloalkanes with suitable examples.
                  \nAnswer:
                  \nSN1<\/sup><\/sub> stands for unimolecular nucleophilic substitution
                  \n\u2018S\u2019 stands for substitution
                  \n\u2018N\u2019 stands for nucleophilic
                  \n\u20181\u2019 stands for unimolecular (one molecule is involved in the rate-determining step)
                  \nThe rate of the following SN1<\/sup><\/sub> reaction depends upon the concentration of aikyl halide (RX) and is independent of the concentration of the nucleophile (OH-).
                  \nRate of the reaction = k[alkyl halide]
                  \nR – Cl + OH–<\/sup> \u2192 R – OH + Cl–<\/sup>
                  \nThis SN1<\/sup><\/sub> reaction follows first order kinetics and occurs in two steps.
                  \nWe understand SN1<\/sup><\/sub> reaction mechanism by taking a reaction between tertiary hutyl bromide with aqueous KOH.
                  \n\"Samacheer<\/p>\n

                  This reaction takes place in two steps aas shown below.<\/p>\n

                  Step – 1:
                  \nFormation of carbocation:
                  \n\"Samacheer
                  \nt – butyl bromide<\/p>\n

                  The polar C – Br bond breaks forming a carbocation and bromide ion. This step is slow and hence it is the rate-determining step.<\/p>\n

                  Step 2:
                  \nNucleophilic attack on carbocation
                  \nThe carbocation immediately reacts with the nucleophile. This step is fast and hence does not affect the rate of the reactions.
                  \n\"Samacheer<\/p>\n

                  As shown above, the nucleophilic reagent OH~ can attack carbocation from both the sides, they will be a mirror image of each other.<\/p>\n

                  In the above example, the substrate tert-butyl bromide is not optically active, hence the obtained product is optically inactive. If halo alkane substrate is optically active then, the product obtained will be an optically inactive racemic mixture. As nucleophilic reagent OH- can attack carbocation from both the sides, to form an equal proportion of dextro and levorotatory optically active isomers which form optically inactive racemic mixture.<\/p>\n

                  Example: Hydrolysis of optically active 2- Bromo butane gives racemic mixture of \u00b1butan-2-ol.<\/p>\n

                  Question 3.
                  \nExplain the E2<\/sub> reaction mechanism with a suitable example.
                  \nAnswer:
                  \nE2<\/sub> stands for bimolecular elimination reaction
                  \n\u2018E\u2019 stands for elimination
                  \n\u20182\u2019 stands for bimolecular
                  \nThe rate of E2<\/sub> reaction depends on the concentration of alkyl halide and base<\/p>\n

                  Rate = k2<\/sub> [alkyl halide] [base]
                  \nIt is therefore, a second-order reaction generally primary alkyl halide undergoes this reaction in the presence of alcoholic KOH. E2<\/sub> is a one-step process in which the abstraction of the proton from the p carbon and expulsion of halide from the carbon occurs simultaneously. The mechanism is shown below.
                  \n\"Samacheer<\/p>\n

                  \"Samacheer<\/p>\n

                  Question 4.
                  \nExplain the E1<\/sub> reaction mechanism with a suitable example.
                  \nAnswer:
                  \nE1<\/sub> stands for unimolecular elimination reaction
                  \n‘E’ stands for elimination ‘1’ stands for unimolecular
                  \nThe rate of E1<\/sub> reaction depends on the concentration of alkyl halide only and hence
                  \nrate = k [alkyl halide]
                  \nGenerally, tertiary alkyl halide which undergoes elimination reaction by this mechanism in the presence of alcoholic KOH following first order kinetics is a two step process. The mechanism is shown by taking following example.
                  \n\"Samacheer<\/p>\n

                  step – 1:
                  \nHeterolytic fission to yield a carbocation:
                  \n\"Samacheer<\/p>\n

                  Step – 2:
                  \nElimination of a proton from the \u03b2 – carbon to produce an alkene:
                  \n\"Samacheer<\/p>\n

                  Question 5.
                  \nHow are the following compounds prepared from Methyl magnesium iodide?
                  \n(i) Ethanol
                  \n(ii) Tert-butyl alcohol
                  \n(iii) Acetaldehyde
                  \nAnswer:
                  \n(i) Ethanol:
                  \nFormaldehyde reacts with methyl magnesium iodide to give addition products which on hydrolysis yield ethanol.
                  \n\"Samacheer<\/p>\n

                  (ii) Tert-butyl alcohol:
                  \nAcetone reacts with methyl magnesium iodide to give an additional product which on hydrolysis yields tert butyl alcohol.
                  \n\"Samacheer<\/p>\n

                  (iii) Acetaldehyde:
                  \nEthyl formate reacts with methyl magnesium iodide and followed by acid hydrolysis, it forms Acetaldehyde.
                  \n\"Samacheer<\/p>\n

                  Question 6.
                  \nHow is ethylene dichloride converted into
                  \ni) Acetaldehyde
                  \nii) Ethylene glycol
                  \nii) Ethylene
                  \nAnswer:
                  \ni) Acetaldehyde:
                  \n(Hydrolysis with aqueous NaOH or KOH)
                  \nEthylidene chloride reacts with aqueous KOH to give acetaldehyde.
                  \n\"Samacheer<\/p>\n

                  ii) Ethylene glycol :
                  \nEthylene chloride reacts with aqueous KOH, it gives glycol.
                  \n\"Samacheer<\/p>\n

                  iii) Ethylene:
                  \nEthylene dichloride is heated with Zinc in presence of methanol gives ehtylene.
                  \n\"Samacheer<\/p>\n

                  \"Samacheer<\/p>\n

                  Question 7.
                  \nHow are the following compounds prepared from chloroform?
                  \n(i) Phosgene
                  \n(ii) Methylene chloride
                  \n(iii) Methyl isocyanide
                  \nAnswer:
                  \n(i) Phosgene:
                  \nChloroform undergoes oxidation in the presence of light and air to form phosgene (carbonyl chloride)
                  \n\"Samacheer
                  \nSince phosgene is very poisonous, its presence makes chloroform unfit for use as an anaesthetic.<\/p>\n

                  (ii) Methylene chloride:
                  \nChloroform undergoes reduction with zinc and HCl in the presence of ethyl alcohol to form methylene chloride.
                  \nCHCl3<\/sub> (Chloroform) + 2(H) \"Samacheer CH2<\/sub>Cl2<\/sub> (Methylene chloride)+ Cl2<\/sub><\/p>\n

                  (iii) Methyl isocyanide:
                  \nChloroform reacts with an aliphatic or aromatic primary amine and alcoholic caustic potash, to give foul-smelling alkyl isocyanide (carbylamines).
                  \nCH3<\/sub>NH2<\/sub> \u00a0 \u00a0+\u00a0 \u00a0 \u00a0CHCl2<\/sub>\u00a0+ 3KOH \u2192 CH3<\/sub>NC + 3KCl + 3H2<\/sub>O
                  \nMethylamine Chloroform\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Methyl isocyanide<\/p>\n

                  Question 8.
                  \nDiscuss the aromatic electrophilic substitutions reaction of chlorobenzene.
                  \nAnswer:
                  \n\"Samacheer<\/p>\n","protected":false},"excerpt":{"rendered":"

                  Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Chemistry Guide Pdf Chapter 14 Haloalkanes and Haloarenes Text Book Back Questions and Answers, Notes. Tamilnadu Samacheer Kalvi 11th Chemistry Solutions Chapter 14 Haloalkanes and Haloarenes 11th Chemistry Guide Haloalkanes and Haloarenes Text Book Back Questions and Answers Textbook Evaluation: I. Choose the best answer: Question 1. …<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[6],"tags":[],"class_list":["post-37348","post","type-post","status-publish","format-standard","hentry","category-class-11"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/posts\/37348"}],"collection":[{"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/comments?post=37348"}],"version-history":[{"count":1,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/posts\/37348\/revisions"}],"predecessor-version":[{"id":41761,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/posts\/37348\/revisions\/41761"}],"wp:attachment":[{"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/media?parent=37348"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/categories?post=37348"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/samacheerkalvi.guide\/wp-json\/wp\/v2\/tags?post=37348"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}