NEET Haloalkanes and Haloarenes PYQ practice sheet

12 previous-year NEET Chemistry questions from Haloalkanes and Haloarenes, newest papers first. Haloalkanes and Haloarenes carries 11 of the Chemistry questions in NEET 2020 to 2026, so this is a good place to test yourself after revising the chapter. Marking: +4 correct, −1 wrong.

1. 1.

   NEET 2026

   In the following reaction sequence, X and Z respectively are: $\mathrm{CH_3CH_2CH_2-OH+PCl_5\to CH_3CH_2CH_2Cl+X+HCl}$. The chloride on heating with alc. KOH gives Y, and Y reacts with HBr in the presence of benzoyl peroxide to give Z.

   • (A)
     X = $\mathrm{H_3PO_3}$; Z = $\mathrm{CH_3CH_2CH_2-Br}$
   • (B)
     X = $\mathrm{POCl_3}$; Z = $\mathrm{CH_3-CHBr-CH_3}$
   • (C)
     X = $\mathrm{H_3PO_3}$; Z = $\mathrm{CH_3-CHBr-CH_3}$
   • (D)
     X = $\mathrm{POCl_3}$; Z = $\mathrm{CH_3CH_2CH_2-Br}$
2. 2.

   NEET 2026

   The number of chlorine atoms present in the organic products X and Y of the following reactions, respectively, are:

   • (A)
     6 and 6
   • (B)
     3 and 6
   • (C)
     6 and 3
   • (D)
     3 and 3
3. 3.

   NEET 2024

   The compound that will undergo $\mathrm{S_N1}$ reaction with the fastest rate is

   • (A)
     
   • (B)
     
   • (C)
     
   • (D)
     
4. 4.

   NEET 2024

   The products A and B obtained in the following reactions, respectively, are $\mathrm{3ROH+PCl_3\to3RCl+A}$ $\mathrm{ROH+PCl_5\to RCl+HCl+B}$

   • (A)
     $\mathrm{H_3PO_3}$ and $\mathrm{POCl_3}$
   • (B)
     $\mathrm{H_3PO_4}$ and $\mathrm{POCl_3}$
   • (C)
     $\mathrm{POCl_3}$ and $\mathrm{H_3PO_4}$
   • (D)
     $\mathrm{POCl_3}$ and $\mathrm{H_3PO_3}$
5. 5.

   NEET 2024

   Major products A and B formed in the following reaction sequence, are (2-methylcyclohexanol is treated with $\mathrm{PBr_3}$ to give A (major), which on heating with alcoholic KOH gives B (major).)

   • (A)
     
   • (B)
     
   • (C)
     
   • (D)
     
6. 6.

   NEET 2023

   The given compound $\mathrm{C_6H_5{-}CH{=}CH{-}CH(X){-}CH_2CH_3}$ (a benzene ring attached to a $\mathrm{CH{=}CH}$ unit; the next carbon carries the halogen $X$ and an ethyl group) is an example of ________.

   • (A)
     vinylic halide
   • (B)
     benzylic halide
   • (C)
     aryl halide
   • (D)
     allylic halide
7. 7.

   NEET 2023

   Identify the final product [D] obtained in the following sequence of reactions.

   $$\mathrm{CH_3CHO \xrightarrow[ii)\ H_3O^+]{i)\ LiAlH_4} [A] \xrightarrow[\Delta]{H_2SO_4} [B] \xrightarrow{HBr} [C] \xrightarrow[\mathrm{Na/dry\ ether}]{\text{bromobenzene}} [D]}$$

   • (A)
     $\mathrm{HC{\equiv}C^{\ominus}\,Na^+}$
   • (B)
     Ethylbenzene ($\mathrm{C_6H_5{-}CH_2CH_3}$)
   • (C)
     Biphenyl ($\mathrm{C_6H_5{-}C_6H_5}$)
   • (D)
     $\mathrm{C_4H_{10}}$
8. 8.

   NEET 2022

   The incorrect statement regarding chirality is:

   • (A)
     A racemic mixture shows zero optical rotation.
   • (B)
     $S_N1$ reaction yields 1:1 mixture of both enantiomers.
   • (C)
     The product obtained by $S_N2$ reaction of haloalkane having chirality at the reactive site shows inversion of configuration.
   • (D)
     Enantiomers are superimposable mirror images of each other.
9. 9.

   NEET 2022

   Which of the following sequence of reactions is suitable to synthesize chlorobenzene?

   • (A)
     aniline, HCl, heating
   • (B)
     benzene, $\mathrm{Cl_2}$, anhydrous $\mathrm{FeCl_3}$
   • (C)
     phenol, $\mathrm{NaNO_2}$, HCl, CuCl
   • (D)
     benzene, HCl
10. 10.

    NEET 2021

    The correct sequence of bond enthalpy of 'C–X' bond is :

    • (A)
      $\mathrm{CH_3-Cl > CH_3-F > CH_3-Br > CH_3-I}$
    • (B)
      $\mathrm{CH_3-F < CH_3-Cl < CH_3-Br < CH_3-I}$
    • (C)
      $\mathrm{CH_3-F > CH_3-Cl > CH_3-Br > CH_3-I}$
    • (D)
      $\mathrm{CH_3-F < CH_3-Cl > CH_3-Br > CH_3-I}$
11. 11.

    NEET 2021

    The major product formed in dehydrohalogenation reaction of 2-Bromo pentane is Pent-2-ene. This product formation is based on ?

    • (A)
      Hund's Rule
    • (B)
      Huckel's Rule
    • (C)
      Hofmann Rule
    • (D)
      Saytzeff's Rule
12. 12.

    NEET 2020

    Elimination reaction of 2-Bromo-pentane to form pent-2-ene is : (a) $\beta$-Elimination reaction (b) Follows Zaitsev rule (c) Dehydrohalogenation reaction (d) Dehydration reaction

    • (A)
      (a), (b), (c)
    • (B)
      (a), (c), (d)
    • (C)
      (b), (c), (d)
    • (D)
      (a), (b), (d)