Question

Given that ΔH = 0 for mixing of two gases. Explain whether the diffusion of these gases into each other in a closed container is a spontaneous process or not?

Answer 1

It is spontaneous process. Although enthalpy change is zero but randomness or disorder (i.e., ΔS ) increases. Therefore, in equation ΔG = ΔH – TΔS, the term TΔS will be negative. Hence, ΔG will be negative.