Question
Explain the term adsorption. How does adsorption differ from absorption? What are the different types of adsorption?
Solution
The accumulation of molecular species
at the surface rather than in the bulk of a solid or liquid is termed adsorption. The molecular species or substance, which concentrates or accumulates at the surface is termed adsorbate and the material on the surface of which the adsorption takes place is called adsorbent.
|
ADSORPTION |
ABSORPTION |
| It is surface phenomenon i.e. it occurs only at the surface of the adsorbent. | It is bulk phenomenon i.e. it occurs throughout the body of the material. |
| In this phenomenon, the concentration on the surface of adsorbent is different from that in the bulk. | In this phenomenon, the concentration is same throughout the material. |
| Its rate is high in the beginning and then decreases till equilibrium is attained. | Its rate remains same throughout the process. |
