## HW 9.13

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

William_Lee_Dis_3H
Posts: 15
Joined: Wed Sep 21, 2016 2:57 pm

### HW 9.13

When calculating the entropy change due to the change in temperature, where does the the equation delta S = n R ln (t2/t1) come from in the solutions manual? Shouldn't the equation be delta S = n C ln(t2/t1)? And how are we supposed to assume that there are 1.00 moles of N2 gas without the problem explicitly stating it?

Parsia Vazirnia 2L
Posts: 44
Joined: Fri Jul 22, 2016 3:00 am

### Re: HW 9.13

I second this. I need help on this problem as well.

Chem_Mod
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### Re: HW 9.13

Since this question asks you to assume that the N2 exhibits ideal gas behavior, the variation of the entropy equation $\Delta$S= nRln(T2/T1). Additionally, since the question mentions that the gas is ideal and no number of moles is otherwise specified, the number of moles in the container is implied to be 1 mole. For more information on this, refer to pg. 323.

Jessica Chern 1H
Posts: 22
Joined: Sat Jul 09, 2016 3:00 am

### Re: HW 9.13

I thought that the equation using R was only for volume or pressure (ΔS = nR ln(V2/V1)). Is it the same for temperature too? Where did that equation come from?