Chemical potential of an ideal gas problem

arenaninja
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Hey everyone. I hope someone can help. I'm off on this by several factors so I'm wondering what I may be inferring incorrectly.

Homework Statement


Express the chemical potential of an ideal gas in termps of T and V:
\mu = c_{P}T - c_{V}T\ln T - RT\ln V - s_{0}T + const

Homework Equations


(Hint: Find the entropy S = S(T,V); use G = U - TS + PV and write \mu = G/n)

The Attempt at a Solution


For S = S(T,V) of an ideal gas we have:
S = nc_{V}\ln T + nR\ln V
Now we attempt to find G:
G = U - TS + PV
Recognize that U for an ideal gas is a constant (Nfk/2), and we have:
G = -nc_{V}T\ln T - nRT\ln V + \frac{nfk_{B}}{2} + PV

As you can see, I'm missing two terms. I'm not sure how PV would translate into those two terms. So overall I'm not faring very well in this problem.

Any hints? Insights? Corrections?
 
Last edited:
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What is PV for an ideal gas?
 
PV = nRT
Also, for ideal gases:
c_{P} = c_{V} + nR
Ohhh I see (I think). So the last term:
nk_{B}T = c_{P}T - c_{V}T

I'm guessing c_{V}T = s_{0}T. Great!

Thank you very much!
 
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