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What is the entropy change of a

**working substance**taken around 1) a completely reversible closed cycle and 2) a closed cycle containing irreversible steps? Explain your reasoning.

Now this question has me a tad confused. I think that for part 1 the entropy change is zero. My reasoning was that if you take the substance along some reversible path, say from 1 to 2, giving an entropy change of ds(1 to 2) then to go back along would give an entropy change of -ds(1 to 2). If that make sense.

For part 2, i think ds could be > 0 or < 0. My reasoning is that the entropy change for the 'universe' must be > 0 but that the change in entropy for the working substance could be positive or negative, as long as the entropy change of the system + surroundings is > 0 .

Hope thats clear.

Any ideas?

Thanks