'Adsorption' principle is used for which of the following purification method?

Solution

Chemistry ma’am · 3 steps

Ask what each method separates on: chromatography sorts components by how tightly they stick to a surface.

1. What adsorption means. Adsorption is molecules sticking to the surface of a solid, such as silica gel or alumina. Different compounds stick with different strengths.
2. Match each method. Every purification method rests on one physical difference between the components. Check which method uses surface attraction.

   Method	Principle it uses
   Chromatography	Adsorption on a stationary phase (or partition between two phases)
   Sublimation	Solid turns directly into vapour on heating
   Distillation	Difference in boiling points
   Extraction	Difference in solubility in two immiscible solvents

3. So. In column or thin-layer chromatography, the weakly adsorbed component moves faster with the mobile phase and the strongly adsorbed one lags behind. The answer is (a), chromatography.

The idea to keep. Tie each purification method to its principle: chromatography to adsorption or partition, distillation to boiling point, extraction to solubility, sublimation to solid-to-vapour change.

Answer from the NTA final answer key. Solution by PrepWiser.