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

The molar energy of a monatomic gas which obeys van der Waals' equation is given by

E = (3/2)RT - a/V

V volume, T temperature, a is a constant. Initially you have T1 at V1, and the gas expands adiabatically in a vacuum so that you have V2. What is T2?

2. Relevant equations

Van der Waals' equation: P = RT/(V - b) - a/V^2

3. The attempt at a solution

Q = 0, so dW = dE. dW = -PdV, and I rewrite P in terms of V and T according to van der Waals' equation, then try to rearrange terms so that I can integrate, but I don't think the terms are separable, and I'm beginning to wonder if there is something wrong in my approach. Any help would be appreciated.

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# Homework Help: Adiabatic expansion of a monatomic gas

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