Here is the problem:(adsbygoogle = window.adsbygoogle || []).push({});

"A careless experimenter left the valve of a tank of helium slightly open over the weekend. The gas, originally at 200 atm, slowly escaped isothermally at 20 degrees C. What change in entropy per kg of gas occured? " I am given, K, N, and Mass of helium per mole.

I am stuck because all I know is:

Delta S = N k Ln[Vf/Vi]

and

P=NkT/V

I can't seem to figure out how to make these work though given the problem at hand. How do I find out what N-final and V-final are? That is assuming I even need to find those out to solve this problem. :uhh: Any help is greatly appreciated!

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# Homework Help: Entropy problem(Thermo)

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