Aliphatic and Aromatic Functional Groups:
Functional groups can be classified as
1. Aliphatic or
2. Aromatic.
An aliphatic functional group is one in which there is no aromatic ring directly related to the functional group.
Figure: (a) Aliphatic ketone; (b) aliphatic ester; (c) aromatic carboxylic acid; (d) aromatic ketone.