What is the Sackur-Tetrode expression for the entropy of a monatomic ideal gas?

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The Sackur-Tetrode expression for the entropy of a monatomic ideal gas is derived using the equations for pressure, temperature, and internal energy. The user successfully substituted values for volume and internal energy, arriving at the expression S = Nk[ln(KT/P(2πmT/h²)^(3/2)) + 5/2]. However, feedback indicates that the expression may be missing factors of the Boltzmann constant K and suggests combining K and T for clarity. The user seeks confirmation of their solution before proceeding with the next part of the problem. Overall, the discussion emphasizes the importance of accuracy in deriving thermodynamic equations.
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Homework Statement


Write the Sackur-Tetrode expression for the entropy of a monatomic ideal gas as a function of pressure, temperature, and number, S(N,T,P).


Homework Equations


S = Nk[ln(V/N(4πmU/3Nh2)3/2) + 5/2]
PV = NkT
U = (f/2)NkT


The Attempt at a Solution


I found that equation for S in my book and also found that f = 3 for monatomic gases. So I used V = NkT/P and U = (3/2)NkT and just put it into the equation for S to get:
S = Nk[ln(KT/P(2πmT/h2)3/2) + 5/2].

I just wanted to see if I got this right because sometimes I make stupid mistakes and I didn't want to continue to the next part of the problem if got this part incorrect.
 
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Hello.

Looks pretty good, but I don't think you have enough factors of K in your expression. Also, you might want to combine all factors of K and T to make it look a little nicer.
 
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