Question

Which of the following is NOT TRUE for the adsorption of a gas on a solid?

• A. Increase in temperature favours adsorption
• B. Enthalpy change is negative
• C. Adsorption is a surface phenomenon
• D. Entropy change is negative

Answer 1

Answer: (A)

Adsorption is a Process involving equilibrium between two opposing processes adsorption and desorption.
Gas (adsorbate) + Solid (adsorbent) $\rightleftharpoons$ Gas adsorbed on solid + Heat
As the forward process (adsorption) is exothermic, according to Le Chatelier's principle, it will decrease with increase in temperature.