Give one chemical test of distinguish between the following pairs of compounds.
Ethylamine and aniline

Explanation

Ethyl amine (`1^(@)` - aliphatic amine) and aniline (`1^(@)` - aromatic amine) are distinguished by Diazotisation reaction. Aniline under go diazotisation reaction to form benzene diazonium salt where as ethyl amine form highly unstable alkyl diazonium salt
`C_(6)H_(5)NH_(2) overset(NaNO_(2)+HCl) to underset("Benzene diazonium chloride")(C_(6)H_(5)N_(2)^(+)Cl^(-)+3NaCl+2H_(2)O)`