A solid on boiling with aqueous NaOH liberates a gas that turns moist red litmus blue. Acidifying the residual solution gives a white precipitate. The solid is

Amide hydrolysis gives ammonia, which is basic and turns red litmus blue, and sodium benzoate, which gives white benzoic acid on acidification. Methyl benzoate gives methanol, benzoic acid gives no gas, and acetophenone is unaffected.