Define the following:

(a) Sol


(b) Aerosol


(c) Emulsion


(d) foam

(a) Colloidal solution is called sol when liquid is dispersing medium and solid is dispersed phase. For example – blood, ink, paint, etc.

(b) When particles of solid or liquid dispersed in gaseous medium, the mixture is known as Aerosol. For example – cloud, smog, smoke etc.


(c) Colloidal solution is called emulsion, when dispersing medium and dispersed phase both are liquid. For example – milk, butter, face cream, etc.


(d) Mixtures are called foam when liquid is present as dispersing medium and gas is dispersed medium. For example – shaving cream, soap bubbles, etc.


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