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

The van der Waals’ equation of state for one mole of gas is given by

(P+a/V^{2})(V-b)=RT

where V is the molar volume at temperature T, and a and b are constants. The internal energy of the gas is given by

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

Initially, one mole of the gas is at a temperature T1 and occupies a volume V1. The gas is allowed to expand adiabatically into a vacuum so that it occupies a total volume V2. What is the final temperature of the gas?

2. Relevant equations

3. The attempt at a solution

I guess the energy of the gas is constant as it is an adiabatic expansion(right?..).

So E_{1}=E_{1}and so T_{2}=T_{1}+2a/(3R)(1/V_{2}-1/V_{1})

Do I need the first equation provided?

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# Homework Help: Thermodynamic Question

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