(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://img812.imageshack.us/img812/1874/entropy.jpg [Broken]

3. The attempt at a solution

First, not sure if this is an adequate explanation but I think for both gases in both partitions, regardless of whether it starts off colder or warmer, the total entropy will increase in order to reach thermal equilibrium.

To find the final temprature, I have an equation in my notes for the final temprature when an object and its environment come in contact and reach a final temperature:

[itex]T_f = \frac{C_oT_o + C_eT_e}{C_o+C_e}[/itex]

Is this the correct equation for this situation? And what kind of heat capacities are the C's (C_{v}or C_{p})?

For the total entropy I would use the equation which gives the total change of entropy by the object+environment:

[itex]\Delta S_{o+e} = \Delta S_o + \Delta S_e = Q_{tot} \left( \frac{1}{T_o} - \frac{1}{T_e} \right)[/itex]

And there is another equation:

[itex]\Delta S_{o+e} = C_o \ln \left( \frac{T_f}{T_o} \right) + C_e \ln \left( \frac{T_f}{T_e} \right)[/itex]

I want to use the second one. But again how do I find the C_{e}and C_{o}? The only info I am given is the number of moles. Any guidance is appreciated.

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# Homework Help: Entropy and Final Temperature

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