What are emulsion ? How are they classified ? Describe the applications of emulsions.

Explanation

Emulsion : The colloidal system in which a dispersion of finely divided droplets of a liquid in another liquid medium is called emulsion. Eg : Milk.
In Milk, the droplets of a liquid fat are dispersed in water. This is an example for oil in water type emulsion.
Classification of emulsions : Emulsions are classified into two classes. These aer
a) Oil in water (O/W) and
b) Water in Oil (W/O) , (O=Oil, W=Water)
These emulsions are classified as such depending on which is dispersed phase is oil and the dispersion medium.
a) Oil in Water (O/W) type emulsions : In This type of emulsions , the dispersed phase is oil and the dispersion medium is water.
Ex : Milk , liquid, fat (oil) in water
Vanishing cream, fat in water.
b) Water in Oil (W/O) type emulsions : In this type of emulsions, the dispersed phase is water and the dispersion medium is oil
Ex : Stiff greases : Water in lubrication oils.
Cod liver oil : water in cod liver oil
Cold cream : water in fat.
Applications of Emulsions : Emulsions are useful
`to` In the digestion of fats in intestines.
`to` In washing processes of clothes and crockery.
`to` In the preparation of lotions, creams , ointments in pharmaceutical and cosmetics .
`to` In the extraction of metals (froth floatation).
`to` In the conversion of cream into butter by churing
`to` To break oil and water emulsions in oil wells.
`to` In the preparation of oily type of drugs for easy adsorption to the body.