Assertion (A): Acetanilide is a far weaker base than aniline. Reason (R): In acetanilide the nitrogen lone pair is delocalised towards the carbonyl oxygen in addition to the benzene ring.

Answer: B

Aniline has pKaH 4.6 while acetanilide is protonated only in strong acid (pKaH about

- 1

). The

N - C = O

amide resonance competes with the ring for the lone pair, which makes it much less available; R correctly explains A.

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