Question

Which of the following statements are correct?
A. The $C-Cl$ bond in chlorobenzene is shorter than in chloromethane.
B. It is difficult to replace chlorine from chlorobenzene than from benzyl chloride.
C. The $C-Cl$ bond in chlorobenzene has some double bond character.
D. Chlorobenzene on chlorination gives $m$ -dichlorobenzene

• A. A, B, C
• B. A , D only
• C. B , C , D
• D. C, D only

Answer 1

Answer: (A)

In chlorobenzene lone pair of $e^{-}$ is involved in delocalisation hence double bond character is present in $C-Cl$ bond. Therefore, bond length becomes short. While in $C{H}_{3}Cl$ is delocalisation is absent.

Chlorobenzene has double bond character between $C$ and $Cl$. So, it is difficult to replace form than form benzyl chloride.

(c) $C-Cl$ has double bond character in chlorobenzene.

(d) Chlorobenzene on chlorination gives $m$ -dichlorobenzene due to $o/p$ -directing effect of $Cl$.