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Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: throllen on September 26, 2009, 09:29:11 PM

Title: 3 different concentrations of hydrogen, separate by stopcock
Post by: throllen on September 26, 2009, 09:29:11 PM
0.6 moles, 0.3 moles and 0.1 moles of H2 gas are placed in separate vessels each at 1 atm pressure and 300K.  These vessels are initially connected by stopcocks which are then opened. Assume H2 is an ideal gas. Calculate q, w delta(U, H, S, A and G)


Attempted solution:

Since its all H2 in there, the process is reversible. For ideal gas, since temp is constant. deltaU = 0 and that makes q=w. W=n1RTln(V2/V1)+n2RTln(V2/V1)+n3RTln(V2/V1). Final volume is 100%, so V1 should be 60%, 30% and 10%, but I am wrong...