Explain the term emulsions and types of emulsions.

i. A colloidal system in which one liquid is dispersed in another immiscible liquid is called an emulsion.

ii. There are liquid-liquid colloidal systems in which both liquids are either completely or partially immiscible.

iii. There are two types of emulsions :

a. Emulsion of oil in water (o/w type) : 

An emulsion in which dispersed phase is oil and dispersion medium is water is called emulsion of oil in water.

e.g.,

1. Milk consists of particles of fat dispersed in water.

2. Other examples include vanishing cream, paint, etc.

b. Emulsion of water in oil (w/o type) : 

An emulsion in which dispersed phase is water and dispersion medium is oil is called emulsion of water in oil.

e.g.,

1. Cod liver oil consists of particles of water dispersed in oil.

2. Some other examples of this type include butter, cream, etc.