Which amine forms a precipitate with benzenesulphonyl chloride that is insoluble in excess NaOH?
Secondary amines like CH₃NHCH₂CH₃ form sulphonamides insoluble in alkali, unlike primary amines, as per the PDF’s Hinsberg test.
Ref: NCERT Class 12 Chemistry > Chapter 13: Amines > Topic: Chemical Reactions - Alkylation, Acylation and Electrophilic Substitution