Question

Distinguish between chemical and physical adsorption.

Answer 1

Physical adsorption	Chemical adsorption
Weak van der Waals forces are present between adsorbate and adsorbent.	Strong chemical (covalent) bonds are formed between adsorbate and adsorbent.
It has low heat of adsorption (20 to 40 kJ/mol).	It has high heat of adsorption (40 to 200 kJ/mol).
Multilayers of adsorbed particles are formed.	Monolayer of adsorbed particles is formed.
It is not specific in nature.	It is specific in nature.