Question

Explain the following:

The physical adsorption decreases with an increase in temperature.

Answer 1

1. Physical adsorption involves weak van der Waals’ forces between gas molecules and the solid surface.
2. These forces are stronger at lower temperatures because molecules have less kinetic energy and stay closer to the surface.
3. When temperature increases, gas molecules gain more kinetic energy and move faster.
4. As a result, molecules overcome the weak attractive forces and escape from the surface more easily.

Hence, the amount of physically adsorbed gas decreases as temperature rises.