Question

Reaction of nitrous acid with aliphatic primary amine in the cold gives

Answer 1

Nitrous acid ( HNO2 or HONO ) reacts with aliphatic amines in a fashion that provides a useful test for distinguishing primary, secondary and tertiary amines.

1°-Amines + HONO (cold acidic solution) → Nitrogen Gas Evolution from a Clear Solution
2°-Amines + HONO (cold acidic solution) → An Insoluble Oil (N-Nitrosamine)
3°-Amines + HONO (cold acidic solution) → A Clear Solution (Ammonium Salt Formation)....
.
.

Answer 2

$\huge\textcolor{orange}{\rm{Answer :-}}$

●Aliphatic primary amines also react with $HNO_2$ at 273–278 K to form aliphatic diazonium salts. However, these are unstable even at low temperature and therefore, decompose readily to form alcohols (generally predominate) and $N_2$ is evolved.