Solubility of liquids in liquids

 Liquid-liquid systems may be divided into 2 categories:

1)Systems showing complete miscibility such as alcohol & water, glycerin & alcohol, benzene & carbon tetrachloride..

2) Systems showing Partial miscibility as phenol and water;

two liquid layers are formed each containing some of the other liquid in the dissolved state.

Complete miscibility occurs when:

The adhesive forces between different molecules (A-B) >> cohesive forces between like molecules (A-A or B-B).

Partial miscibility results when:

Cohesive forces of the constituents of a mixture are quite different, e.g. water (A) and hexane (B). A-A » B-B.

The non polar molecules (B) will be squeezed out by the powerful attractive forces existing between the molecules of the polar liquid.

The term miscibility refers to the mutual solubility of the components in liquid-liquid systems.