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

Calculate the entropy of mixing for a system of two monatomic ideal gases, A and B ,whose relative proportion is arbitrary. Let N be the total number of molecules and let x be the fraction of these that are of species B. You should find

delta(S) mixing=-Nk[x ln x +(1-x) ln (1-x)

2. Relevant equations

delta (S(total))=delta(S(A)) + delta(S(B))=2Nk ln 2

S=Nk[ln((V/N)(((4*pi*m*U)/3Nh^2)^(3/2))+2.5]

3. The attempt at a solution

according to my thermal physics text, delta(S(A))=Nk ln 2 . The problem says that in species B , x is just a fraction of N. Then , I think I would have to conclude that delta(S(B))=x/N*(k)*ln(2).

so would my expressison be :delta(S(mixing))=delta(S(A))+delta(S(B))=Nk ln 2+ xk/N*(ln(2))

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# Determining an expression for an entropy equation

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