(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

Using the Carnahan and Starling equation, estimate the coefficient of volumetric expansion, α, and the coefficient of compressibility, β, defined as

α ≡ 1/V * (δV/δT) [holding P constant] and

β ≡ -1/V * (δV/δP) [holding T constant]

(I've used δ here for partial differentials)

for the hard sphere fluid at a packing fraction η = 0.40.

3. The attempt at a solution

I've tried using Z = PV/nkT and then the CS expression for Z: Z = (1+η+η²-η³) / (1-η)³ however we find α = 1/T and β = 1/P which seems far too easy.

Could someone please offer a suggestion of which direction I should be looking in? Any help would be greatly appreciated!!

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# Homework Help: Expansion/Compressibility Coefficients: Carnahan & Starling Model

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