Question

Which is an irreversible process?

• A. mixing of two gases by diffusion
• B. evaporation of water at $373K$ and 1 atm pressure
• C. dissolution of $NaCl$ in water
• D. None of these

Answer 1

Answer: (A), (C)

dissolution of $NaCl$ in water
mixing of two gases by diffusion

Irreversible process : Any process which does not take place in the above manner and difference between driving force and the opposing force is quite large is called irreversible process.All natural processes are example of irreversible process.
So dissolution of $NaCl$ in water and mixing of two gases by diffusion are irreversible process.