Statement – I: At equilibrium entropy is zero

Statement–II: At equilibrium change in entropy is maximum

Statement I is incorrect; entropy is not zero at equilibrium. In fact, at equilibrium, a system’s entropy is at a maximum, meaning that it has reached the highest level of disorder it can without external energy being added to the system.

Statement II is correct; at equilibrium, the change in entropy is maximum because the system cannot become more disordered without additional energy. This is in line with the second law of thermodynamics, which states that the total entropy of an isolated system can never decrease over time.