## 2015 Midterm Q4/5 A

$\Delta S = \frac{q_{rev}}{T}$

Yinhan_Liu_1D
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### 2015 Midterm Q4/5 A

We know that in this process delU=3/2 nRdelT, isothermal, so that we could use delS=q/T=-W/T=nRln(V2/V1)

But does anybody know why we can't use delS=kB*ln (V2/V1)? It gives us a very small figure, which is not the same as that calculated in nRln(V2/V1)

Chem_Mod
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### Re: 2015 Midterm Q4/5 A

plank constant gives you the entropy of a single molecule while nR is calculateing the entropy of n moles of the molecules.