Match List-I with List-II.
| List-I State of dispersed phase and dispersion medium | List-II Example of colloidal system |
| a. Dispersed phase : Solid Dispersion medium : Liquid | I. Soap lather |
| b. Dispersed phase : Liquid Dispersion medium : Solid | II. Paints |
| c. Dispersed phase : Gas Dispersion medium : Liquid | III. Pumice stone |
| d. Dispersed phase : Gas Dispersion medium : Solid | IV. Jellies |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → a-II, b-IV, c-I, d-III
Colloids are classified by the physical state of the dispersed phase and of the dispersion medium. A gas mixed with a gas forms a homogeneous mixture, so eight types of colloidal systems are possible, each with its own name:
a. Dispersed phase : Solid, Dispersion medium : Liquid — This matches II. Paints. A solid dispersed in a liquid is a sol; paints and cell fluids are examples.
b. Dispersed phase : Liquid, Dispersion medium : Solid — This matches IV. Jellies. A liquid dispersed in a solid is a gel, as in cheese, butter and jellies.
c. Dispersed phase : Gas, Dispersion medium : Liquid — This matches I. Soap lather. A gas dispersed in a liquid is a foam, as in froth, whipped cream and soap lather.
d. Dispersed phase : Gas, Dispersion medium : Solid — This matches III. Pumice stone. A gas dispersed in a solid is a solid sol, such as pumice stone and foam rubber.
Shortcut: The pair a-II appears only in Option (3).
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
