Question

25. Which is an irreversible process?

1) mixing of two gases by diffusion
2) Evaporation of water at 373k and 2atm
pressure
3) Dissolution of Nacl in water
4) All are correct
(S

Answer 1

3 dissolution of NaCl in water, since chemical changes are irreversible

Answer 2

The answer is 1) mixing of two gases by diffusion.

Once 2 gases are mixed by diffusion, they cannot be obtained from the mixture of gases. Hence, it is considered to be an irreversible process.