Physical adsorption usually involves the formation of a multilayer of adsorbate molecules, while chemical adsorption is usually found to a involve the formation of monolayer of adsorption molecules. Explain the reason.

Explanation

In case of chemisorption , since there is electronic interaction present between adsorbate and adsorbent molecules , only a monolayer of adsorption can be formed on the adsorbent surface. In case of physisorption , the first adsorption formed . In case of physisorption , the first monolayer formed on the surface of the adsorbent can act as adsorbing surface of the adsorbent can act as adsorbing surface for formation of next layer of adsorbate and so on. This phenomenon is called multilayer adsorption.