My lecture notes had S=A{3nR[ln(T)]/2+nR[ln(V)]}. A arbitary, is the entropy equation for a monotomic ideal gas.(adsbygoogle = window.adsbygoogle || []).push({});

The third law demands S->0 as T->0. But as T->0 in the above equation, S -> -infinity assuming V fixed.

What is wrong?

Or is it the case that S-> -infinity is equivalent to minimum entropy?

V can be made arbitarily small but non zero so when T=0, the entropy must be smaller than any S when T is non zero. This can only happen if S-> -infinity as if it's a finite number than V can always be made smaller so that there exists a V and T such that S is smaller than S when zero T.

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# Homework Help: Realisability of the third law?

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