What are amines ? How are they classified ?

Explanation

(i) Amines are compounds derived from ammonia by replacing one or more hydrogen atoms by alkyl or aryl group.
(ii) They are classified as primary, secondary and tertiary amines.
(a) When one of the hydrogen atoms in `NH_3` is replaced by alkyl, it is primary amine `CH_3NH_2` methyl amine `(1^(@))`.
(b) If two hydrogen atoms of amine group are replaced by alkyl groups, it is a secondary amine `(CH_3)_2` NH-dimethylamine `(2^(@))`.
(c ) If three hydrogen atoms of amine group are replaced by alkyl groups, it is a tertiary amine. `(CH_3)_3` N-trimethylamine `(3^(@))`.
Aromatic amine- `C_6H_5NH_2` Aniline.