CBSE Class 12 Chemistry Notes: Amines – Physical Properties

Properties of Amines:

Physical Properties:

1. Among aliphatic amines, the lower members are gases while higher members are liquids. Among arylamines, the lower members are liquids while higher members are solids. Methyl amine and ethylamine have ammonical smell but higher amines have fishy smell. Most of aromatic amines are colourless but become coloured due to oxidation in air.

2. Boiling points:

All amines except tertiary amines are capable of forming intermolecular hydrogen bonds due to the presence of polar N – H bonds.

Due to this, amines have higher boiling points than non – polar compounds of comparable molecular mass. Among isomeric amines, 1o amines have highest boiling point due to more extensive H – bonding while 3o amines have the least boiling point due to their inability to form hydrogen bonds.

3. Solubility:

Aliphatic amines of lower molecular mass are soluble in water. With increase in molecular mass, solubility in water decreases, while that in ether increases.

CBSE Class 12 Chemistry Amines All Topic Notes CBSE Class 12 Chemistry All Chapters Notes