Dispersed phase and dispersion medium for fog are:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → liquid, gas
Fog is a colloid of the aerosol type: tiny droplets of liquid water (dispersed phase) are spread through air (dispersion medium, a gas). Clouds and mist are aerosols of the same kind.
Why the other options are incorrect
Option (1) solid, liquid — Incorrect. A solid dispersed in a liquid is a sol, for example paints and cell fluids.
Option (2) liquid, liquid — Incorrect. A liquid dispersed in a liquid is an emulsion, for example milk.
Option (4) gas, liquid — Incorrect. A gas dispersed in a liquid is a foam, for example froth and whipped cream.
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic is not there in the latest NCERT book (2026-27), and it is also out of the CUET 2026 syllabus.
NCERT (Pre-rationalised edition, 2022-23):
Classification Based on Physical State of Dispersed Phase and Dispersion Medium – …
| Dispersed phase | Dispersion medium | Type of colloid | Examples |
|---|---|---|---|
| Solid | Solid | Solid sol | Some coloured glasses and gem stones |
| Solid | Liquid | Sol | Paints, cell fluids |
| Solid | Gas | Aerosol | Smoke, dust |
| Liquid | Solid | Gel | Cheese, butter, jellies |
| Liquid | Liquid | Emulsion | Milk, hair cream |
| Liquid | Gas | Aerosol | Fog, mist, cloud, insecticide sprays |
| Gas | Solid | Solid sol | Pumice stone, foam rubber |
| Gas | Liquid | Foam | Froth, whipped cream, soap lather |