6.2 - Nitrogen Compounds, Polymers and Synthesis

Question 1

Describe the basicity of amines and their reactions with dilute acids.

Answer 1

The lone pair of electrons on the nitrogen atom form a dative bond with a hydrogen ion. The amine is acting as a base by accepting a proton. E.g. CH3NH2 + HCl –> CH3NH3+Cl-

Question 2

Describe the preparation of primary aliphatic amines.

Answer 2

A primary amine can be made by heating a haloalkane with an excess of ethanolic ammonia. E.g. 2NH3 + CH3CH2Br –> CH3CH2NH2 + NH4+Br-
More than one hydrogen can be substituted, producing a mixture of primary, secondary and tertiary amines and quaternary ammonium salts.