The test to distinguish primary, secondary and tertiary amines is:

Hinsberg reagent (benzene sulphonyl chloride,${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{SO}}_2\mathrm{Cl}$) may be used to distinguish amines.

 Primary amine reacts to given a product which is soluble in $\mathrm{KOH}$ solution.

 Secondary amine also reacts to give product which is insoluble in $\mathrm{KOH}$ solution. Tertiary amine does not react

 Mustard oil test uses ${\mathrm{CS}}_2$ and ${\mathrm{HgCl}}_2$ • Primary amine forms isothiocyanate which has pungent smell like mustard oil

. Secondary and tertiary amine do not react.

 Carbylamine test uses${\mathrm{CHCl}}_3$ and alcoholic $\mathrm{KOH}$. Only primary amine reacts to give isothiocynide having bad