Question

What is the effect of pressure on the adsorption of a gas on a solid?

Answer 1

Effect of temperature depends on the nature of adsorption. In case of physical adsorption it decreases with increase in temperature because it is an exothermic process. In case of chemical adsorption, it first increases and then starts decreasing with increase in temperature.

Answer 2

Answer:

Rate of adsorption of a gas on a solid surface depends on various factors:

(1) Nature of the gas:

There is a strong Van der Waal’s forces in easily liquefiable gases hence, easily liquefiable gases such as NH3, HCl etc. are adsorbed to a great extent in comparison to gases such as H2, O2 etc.

(2) Surface area of the solid

The adsorption rate of a gas on the solid surface increases with the increase in the surface area of the adsorbent.

(3) Effect of pressure

Adsorption increases with an increase in pressure and, as a result adsorption is a reversible process and is accompanied by a decrease in pressure

(4) Effect of temperature

Adsorption is an exothermic process. Thus, in accordance with Le-Chatelier’s principle, the magnitude of adsorption decreases with an increase in temperature.