Dispersed phase
Dispersion medium
Type of colloid
Example
1. 2. 3. 4.
liquid liquid liquid gas
solid gas liquid liquid
gel aerosol emulsion foam
Jelly, butter fog, cloud milk, hair-cream soap, leather
Based on the Nature of Interaction Between Dispersed Phase and Dispersion Medium:
Hydrophilic colloids: These are water-loving colloids. The colloid particles are attracted to the water. They are also known as reversible sols. Examples include Agar, gelatin, pectin, etc
Hydrophobic colloids: These are the opposite in nature to hydrophilic colloids. The colloid particles are repelled by water. They are also called irreversible sols. Examples include Gold sols, clay particles, etc
Based on Type of Particles of Dispersed Phase:
Multimolecular Colloids: A large number of smaller molecules of a substance add on together on mixing and form species that are in the colloidal range.
Macromolecular Colloids: In this colloid, the macromolecule forms a solution with a solvent. The size of particles remains in the range of colloidal particle size. Here, the colloidal particles are macromolecules having a very large molecular mass.
Associated Colloids: Few substances react as strong electrolytes when they are in low concentration, but act as colloidal sols when they are in high concentration. In high concentration, particles aggregate and show colloidal behaviour and these particles are known as the micelles. They are also known as associated colloids. The formation of micelles occurs above a certain temperature and specific concentration. These colloids can be reverted by diluting it.