Question

Define the following :
(a) Sol
(b) Aerosol
(c) Emulsion
(d) Foam
Give one example of each.

Answer 1

(a) Sol: Sol is a colloidal suspension of very small solid particles in a continuous liquid medium. They are quite stable and show Tyndall effect. Examples include blood, pigmented ink and paint.
(b) Aerosol: Aerosol is a colloidal suspension of fine solid particles or liquid droplets in a gas. Examples are clouds and air pollution such as smog and smoke.
(c) Emulsion: Emulsion is a colloid of two or more liquids that are normally immiscible. Examples of emulsions include milk and butter.
(d) Foam: Foam is formed by trapping pockets of gas in a liquid. Examples of foam include beer foam and shaving cream.