## calculation of change in entropy

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

505166714
Posts: 50
Joined: Fri Sep 28, 2018 12:17 am

### calculation of change in entropy

when volume and temperature change at the same time, how can I calculate the overall change of entropy

Jaqueline Monreal 2L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

### Re: calculation of change in entropy

you do both the method for calculating change in volume: deltaS= nR ln(V2/V1) and for change in temperature: change in delta S= C ln(T2/T1) , and then add the two entropies

Tiffany_Cacy_3D
Posts: 70
Joined: Fri Sep 28, 2018 12:24 am

### Re: calculation of change in entropy

Although the both of these seem to be changing at the same time we treat them as though they happen separately. So when calculating volume you act as though your temperature is a constant and when you calculate the temperature you do the same thing. We can take the entropies separately and then add them up because this is a state function.

Ahmed Mahmood 4D
Posts: 72
Joined: Fri Sep 28, 2018 12:28 am

### Re: calculation of change in entropy

You assume that temperature is constant in one case and that volume is constant in the other, then you add the results of both of those equations.