# Why is entropy of system same for reversible and irreversible processes? [closed]

I read that entropy change of universe is zero in a reversible process but positive in a irreversible process,then doesn't it mean that entropy change of system of both the processes must be different?

I also read that in a reversible cycle, entropy change is zero for example a carnot cycle,and entropy change in an irreversible cycle is positive for example if we consider friction in a carnot cycle. Doesn't this show that entropy change of system in both processes is different?

## closed as unclear what you're asking by CuriousOne, ACuriousMind♦, Kyle Kanos, Danu, Qmechanic♦Mar 19 '16 at 9:21

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

• I don't think I understand your question. But note that the change in entropy is zero for a reversible process, not the entropy itself... – lemon Mar 18 '16 at 16:53
• Yes i meant entropy change – Raksh23 Mar 18 '16 at 17:10
• Yes... The entropy change for a reversible versus an irreversible process is different (by definition)... – lemon Mar 18 '16 at 17:12
• I meant the entropy change in both the processes.We say that entropy change is a state function and hence should not depend on path taken. – Raksh23 Mar 18 '16 at 17:13
• That's right, but a reversible process ends up in a different state to an irreversible process, so the paths are necessarily different... – lemon Mar 18 '16 at 17:13