Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Haloalkanes and Haloarenes question

2019 · 12 Apr · Shift 2 · Q3
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Chemistry
  4. /Haloalkanes and Haloarenes
  5. /2019 · 12 Apr · Shift 2 · Q3

Haloalkanes and Haloarenes question

2019 · 12 Apr · Shift 2 · Q3

JEE MainChemistryHaloalkanes and HaloarenesMCQ+4 / −1
Which one of the following is likely to give a precipitate with AgNO3AgNO_3AgNO3​ solution ?
  1. A
    CHCl3CHCl_3CHCl3​
  2. B
    (CH3)3CCl(CH_3)_3CCl(CH3​)3​CCl
  3. C
    CCl4CCl_4CCl4​
  4. D
    CH2=CH–ClCH_2=CH–ClCH2​=CH–Cl
View written solutionFree

Correct answer: B

  1. Principle of the test with AgNO3AgNO_3AgNO3​

    Silver nitrate solution is commonly used to test whether a halide ion can be released from an organic halide.

    • If the compound easily ionizes to give Cl−Cl^-Cl−, Br−Br^-Br−, etc., then a precipitate of silver halide forms.
    • For chloride: Ag++Cl−→AgCl↓Ag^+ + Cl^- \rightarrow AgCl\downarrowAg++Cl−→AgCl↓

    Thus, compounds that undergo easy nucleophilic substitution / ionization with release of halide ion give a precipitate.

  2. Examine each option

    Option A: CHCl3CHCl_3CHCl3​ (chloroform)

    • The chlorine atoms are attached to a carbon bearing hydrogen and three chlorines.
    • It does not ionize easily to release Cl−Cl^-Cl− in AgNO3AgNO_3AgNO3​ solution.
    • Hence, it is not likely to give a precipitate.

    Option B: (CH3)3CCl(CH_3)_3CCl(CH3​)3​CCl (tert-butyl chloride)

    • This is a tertiary alkyl halide.
    • Tertiary halides undergo substitution very easily by the SN1S_N1SN​1 mechanism because they form a stable tertiary carbocation: (CH3)3CCl→(CH3)3C++Cl−(CH_3)_3CCl \rightarrow (CH_3)_3C^+ + Cl^-(CH3​)3​CCl→(CH3​)3​C++Cl−
    • The released Cl−Cl^-Cl− reacts with Ag+Ag^+Ag+: Ag++Cl−→AgCl↓Ag^+ + Cl^- \rightarrow AgCl\downarrowAg++Cl−→AgCl↓
    • Therefore, this compound will give a precipitate.

    Option C: CCl4CCl_4CCl4​ (carbon tetrachloride)

    • This compound does not undergo hydrolysis/ionization easily.
    • No easy release of Cl−Cl^-Cl− occurs.
    • So it is not likely to give a precipitate.

    Option D: CH2=CH−ClCH_2=CH{-}ClCH2​=CH−Cl (vinyl chloride)

    • Here chlorine is attached to an sp2sp^2sp2 hybridized carbon.
    • Vinyl halides are very resistant to nucleophilic substitution because the C−ClC{-}ClC−Cl bond has partial double bond character due to resonance.
    • Hence, it does not readily release Cl−Cl^-Cl−.
    • So it is not likely to give a precipitate.
  3. Conclusion

    Only tert-butyl chloride readily gives Cl−Cl^-Cl− with AgNO3AgNO_3AgNO3​ solution.

    Therefore, the correct option is: B\boxed{B}B​

PreviousNext

More from Haloalkanes and Haloarenes

  • Heating of 2-chloro-1-phenylbutane with EtOK/EtOH gives X as the major product. Reaction of X with Hg(OAc)2​/H2​O followed by NaBH4​ gives Y as the major product. Y is :2019 · MCQ
  • The major product in the following conversion is – Includes diagram2019 · MCQ
  • The major product of the following reaction is : Includes diagram2018 · MCQ
  • The most polar compound among the following is :2018 · MCQ
  • The major product of the following reaction is: Includes diagram2018 · MCQ
  • The major product of the following reaction is : Includes diagram2017 · MCQ
  • The major product of the following reaction is : Includes diagram2017 · MCQ
  • Which of the following compounds will not undergo Friedel Craft’s reaction with benzene ?2017 · MCQ