The entropy of a hot baked potato decreases as it cools Is t

The entropy of a hot baked potato decreases as it cools. Is this a violation of the increase of entropy principle? Explain.

Solution

No. The principle is not voilated because the baked potato is not isolated system. There is heat transfer occuring from the potato to its surroundings (fluids around the potato and the surface it sits on). The potato will decrease in entropy, while the surroundings increase in entropy. The overall result is the generation of entropy when you put both systems together, thus following increase of entropy principle. (Heat transfer is an irreversible pocess, so Sgen >0)