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

Jeremiah Hutauruk
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Joined: Fri Sep 28, 2018 12:28 am

For changes in volume and temperature, do we just simply add them to get the total entropy?

Chem_Mod
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By "them," I'm assuming you mean the entropies due to changes in volume and temperature, in which case yes.

Ava Kjos 1D
Posts: 65
Joined: Fri Sep 28, 2018 12:19 am

Yes. You first assume constant temperature and calculate the change in entropy due to change in volume. Next, assume constant volume and calculate the change in entropy due the change in temperature. Just add these together to find the total change in entropy. (You could also do this the other way around and calculate the change due to temp. and then the change due to volume).

Kirsty Star 2H
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Joined: Fri Sep 28, 2018 12:24 am

If there is a change in volume and in temperature, you split the problem up into two steps, first using the deltaS equation with V2/v1 and then using the equation with T2/T1. These two deltaS values added together are equal to the deltaS of the whole system

Zubair Ahmed 1L
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Since entropy is a state function, you can simply add the entropy of the change in volume and temperature to find the total change in entropy of the system.

Brian Kwak 1D
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