(i) Aniline forms diazonium salt with NaNO2/HCI which gives orange-red dye with β-naphthol. Ethylamine does not give this test.
(ii) Ethylamine gives foul smelling ethyl isocyanide on heating with chloroform and potassium hydroxide solution. Dimethylamine does not give this test.
C2H5NH2 + CHCl3 + 3KOH → C2H5NC + 3KCl + 3H2O