Give one chemical test to distinguish between the following pairs of compounds.

Ethylamine and aniline


Azo-dye test can be used to distinguish ethylamine and aniline.


Azo-dye test: A dye is obtained when aromatic amines react with HNO2 (NaNO2 + dil.HCl) at 0-5°C, followed by a reaction with the alkaline solution of 2-naphthol. The dye is usually yellow, red, or orange in colour. Aliphatic amines give a brisk effervescence due to the evolution of N2 gas under similar conditions.


Reaction:


Ethylamine;



Aniline;


CH3CH2 – NH2 + HONO C2H5OH + N2 + H2O


2
1