Why does physisorption decrease with increase of temperature ?

Explanation

Physisorption is an exothermic process:
`{:("Solid"+,GashArr,"Gas/solid+Heat"),(("Adsorbent"),("Adsorbate"),("Gas adsorbed on solid").):}`
According to Le-Chatelier's principle, if T is increased, equilibrium shifts in the backward direction i.e., gas is released from the surface of solid.