Question

Give the dispersed phase and the dispersion medium in each of the following:
Cheese
Soda water
Smoke

Answer 1

Hint: Phase that is present in colloidal particle shape is called the dispersed phase. The medium the colloidal particles are distributed in is called the medium of dispersion.

Complete step by step answer:
Colloids are mixtures in which microscopically dispersed insoluble particles of one substance are suspended in another substance. The size of suspended particles is very small ranging from 1-1000 nanometers i.e. ${{10}^{-9}}$m. Colloidal solution shows tyndall effect; in which beams of light incident on colloids are scattered due to the interaction between the light and the colloidal particles.
Colloids are classified on the basis of dispersed phase and dispersion medium into different categories like solid sol, gel, emulsion, foam etc. Dispersed phase and dispersion medium are also categorized in lyophilic and lyophobic on the basis of nature of interactions.

Dispersed phase: The phase that is scattered or present in the form of colloidal particles is known as dispersed phase.
Dispersion medium: The medium in which the colloidal particles are dispersed is called dispersion medium.
Cheese: Cheese is made up of fats suspended or dispersed in water.
Dispersed phase: Fat (Solid)
Dispersion medium: Water (Liquid)

Soda water: Soda water generally contains water and gas.
Dispersed phase: Bubbles of soda water (Gas)
Dispersion medium: Water (Liquid)

Smoke: Smoke generally contains unburnt carbon particles. It is a collection of tiny solid, liquid and gas particles.
Dispersed phase: Unburnt particles of smoke (Solid)
Dispersion medium: Gases (Gas)

Note: Colloidal systems can occur in any of the three key states of matter gas, liquid or solid. Dispersed and dispersion medium generally are solute or solvent like which is present in small amounts is known as dispersed phase and other which is present in large manner is known as dispersion medium.