Calculate delta S for the system when the state of 3.00 mol of a monoatmoic perfect gas for which [tex] C_{p,m} = \frac{5}{2} R [/tex] is changed from 298.15K and 1.00 atm to 398.15K and 5.00 atm.(adsbygoogle = window.adsbygoogle || []).push({});

Now [tex] \Delta S = n \ R ln \frac{V_{2}}{V_{1}} + n C_{v} ln \frac{T_{f}}{T_{i}} [/tex]

but when i do that i get an answer that is -36 J/K which is not right the answer given 22.1 J/K.

what am i doing wrong i know that Cp is for constnat pressure but in this case the pressure is not constant! Neither is the volume. (at least it doesnt say otherwise)

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# Homework Help: Please help with entropy

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