How are colloids classified based on their molecular size?

1.	How are colloids classified based on their molecular size?
Answer» Colloids are classified into three types based on their molecular size as described below. i. Multimolecular colloids: In multimolecular colloids, the individual particles consist of an aggregate of atoms or small molecules with size less than 10 pm. e.g. Gold sol consists of particles of various sizes having several gold atoms. Colloidal solution in which particles are held together with van der Waals force of attraction is called multimolecular colloid. e.g. S₈ sulphur molecules ii. Macromolecular colloids: In this type of colloids, the molecules of the dispersed phase are sufficiently large in size (macro) to be of colloidal dimensions. e.g. Starch, cellulose, proteins, polythene, nylon, plastics. iii. Associated colloids or micelles: The substances behave as normal electrolytes at low concentration and associated in higher concentration forming a colloidal solution. The associated particles are called micelles, e.g. Soaps and detergents

Answer»

Colloids are classified into three types based on their molecular size as described below.

i. Multimolecular colloids:

In multimolecular colloids, the individual particles consist of an aggregate of atoms or small molecules with size less than 10 pm. e.g. Gold sol consists of particles of various sizes having several gold atoms.
Colloidal solution in which particles are held together with van der Waals force of attraction is called multimolecular colloid.

e.g. S₈ sulphur molecules

ii. Macromolecular colloids:

In this type of colloids, the molecules of the dispersed phase are sufficiently large in size (macro) to be of colloidal dimensions.

e.g. Starch, cellulose, proteins, polythene, nylon, plastics.

iii. Associated colloids or micelles:

The substances behave as normal electrolytes at low concentration and associated in higher concentration forming a colloidal solution.
The associated particles are called micelles,

e.g. Soaps and detergents

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