I've been struggling with this problem for an hour or so now, and can't seem to find the right answer. Perhaps someone here can help? I would be very grateful. ;)(adsbygoogle = window.adsbygoogle || []).push({});

Two moles of an ideal gas ( = 1.40) expands slowly and adiabatically from a pressure of 5.09 atm and a volume of 12.7 L to a final volume of 30.0 L.

I had to find this stuff first, and I know I have all of it right.

final pressure: 1.528

initial temp: 393.5K

final temp: 279

Find Q, W, dEint.

I know Q is 0, and I know that Work and change in internal Energy are the opposite of eachother, but I can't seem to find the right value for them. I thought work = nRdT, which in this case is:

2*.08214*(393.5-279)=1902.9

However, that answer is wrong according to webassign. There is also a problem in my text book that is the same, except with different numbers, and i tried that one and got it wrong too. Anyone know what I'm doing wrong? Your help is greatly appreciated. :)

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# Homework Help: Question on adiabatic expansion

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