Which one of the following is correct for the adsorption

Question:

Which one of the following is correct for the adsorption of a gas at a given temperature on a solid surface?

  1. $\Delta \mathrm{H}>0, \Delta \mathrm{S}>0$

  2. $\Delta \mathrm{H}>0, \Delta \mathrm{S}<0$

  3. $\Delta \mathrm{H}<0, \Delta \mathrm{S}<0$

  4. $\Delta \mathrm{H}<0, \Delta \mathrm{S}>0$


Correct Option: , 3

Solution:

(i) Adsorption of gas at metal surface is an exothermic process so $\Delta \mathrm{H}<0$

(ii) As the adsorption of gas on metal surface reduces the free movement of gas molecules thus restricting its randomness hences $\Delta \mathrm{S}<0$

Leave a comment