[Statistical Physics] Microstates in a large system/Boltzmann entropy

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SUMMARY

The discussion focuses on estimating the number of microstates in a 1m³ box of nitrogen gas at standard temperature and pressure (S.T.P.) using the Boltzmann entropy formula. The participant calculated the number of molecules, N, as 2.46x10²⁵ and the mass of a nitrogen molecule as 4.652x10⁻²⁶ kg. Using these values, they derived an entropy value of S = 6122 and attempted to calculate the number of microstates, Ω, resulting in a logarithmic value of lnΩ = 4.44x10²⁶. The participant encountered a "math error" when trying to compute Ω due to the extremely large number.

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Homework Statement



For a box containing 1m^{3} of nitrogen at S.T.P., estimate the number of microstates which make up the equilibrium macrostate.


Homework Equations



S = Nk_{b}(ln\frac{V}{N} + \frac{5}{2} + \frac{3}{2}ln\frac{2πmk_{b}T}{h^{2}})

where the entropy of a volume, V , of an ideal gas, containing N molecules of mass m at temperature T

S = k_{b}lnΩ


The Attempt at a Solution



First off I don't know which mass it is asking for in the equation. Is it the mass of each individual molecule? Or the mass of all the molecules? Or the molar mass? Either way I tried them all but still couldn't get an answer.

I first worked out what N was.

40.82 mols in 1m^{3} of an ideal gas
1 mol = 6.022x10^{23}
∴ N = 2.46x10^{25}

I let m = 4.652x10^{-26} kg (the mass of a nitrogen molecule)

Plugging those numbers into the first equation gives entropy, S = 6122

Now I know the number of microstates is going to be huge, but from the second equation:

lnΩ = S/k_{b} = 4.44x10^{26}

∴Ω = e^{4.44x10^{26}}

which brings about a "math error".

Am I going about this in the right way?

Cheers
 
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Maybe a mod could move this into the Advance forum?
 
That seems correct to me, except for the missing units. S=6122 (what units?).
You only get a math error if you try to plug that huge number into a typical calculator. Why wold you do that?
 
Ah that's good then. I just thought it was an unreasonably large number.

JK^{-1}
 

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