9.13 Changes in Entropy


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9.13 Changes in Entropy

Postby Sue_Park_2D » Sun Jan 29, 2017 9:10 pm

I had a question on 9.13.
"During the test of an internal combustion engine, 3.00 L of nitrogen gas at 18.5 C was compressed suddenly (and irreversibly) to 0.500 L by driving in a piston. In the process, the temperature of the gas increased to 28.1 C. Assume ideal behavior. What is the change in entropy of the gas?"

I understand that there are two entropies to calculate to get the total entropy:
- the decrease of entropy caused by the decrease in volume using the equation nR ln(V2/V1)
- the increase of entropy caused by the increase in temperature.....

I thought that we had to use the equation nC ln(T2/T1) but solutions manual uses nR ln (T2/T1) I'm confused as to why we use this equation instead.

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Re: 9.13 Changes in Entropy

Postby Nikhil_Madan_3C » Sun Jan 29, 2017 9:17 pm

You should use C, it is a typo in the solutions manual.
https://lavelle.chem.ucla.edu/wp-conten ... rs_6Ed.pdf

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