How many of the following give foul smell when heated with chloroform and alcoholic caustic potasha) Dimethyl amineb) 3° butyl aminec) 2° propyl amined) Isobutyl amine

The reaction is called carbyl amine test. This is a test to identify both alkyl and aryl primary amines. When a primary amine is heated with chloroform and alcoholic caustic photosh, a foul smelling carbylamine (or) isocyanide (-NC) is obtained. -NH2+CHCl3+3KOH(alc.)→∆-NC+3KCl+3H2Oa) CH3-NH-CH3 . . . . 2o amineb) (CH3)3CNH2 . . . .1o aminec) (CH3)2CHNH2 . . . .1o amined) (CH3)2CHCH2NH2 . . . .1o amineonly (a) cannot give positive carbyl amine test.