Q.
Assertion (A) Electrophilic substitution reactions in haloarene occur slowly and under drastic conditions.
Reason (R) Haloarene are activated as compared to benzene.
Haloalkanes and Haloarenes
Solution:
Halogen atom due to -$I$-effect has some tendency to withdraw electron from benzene ring. So the ring gets deactivated as compared to benzene. Hence, electrophilic substitution reactions in haloarene occur slowly and require more drastic conditions as compared to those in benzene.
