Assuming that the van der Waals equation of state, 

is satisfied by two pure fluids and by their mixture, and that the van der Waals one-fluid rules

with b_ij = b_ji apply to the mixture, derive expressions for

a. The excess volume change on mixing at constant T and P 

b. The excess enthalpy and internal energy changes on mixing at constant T and P 

c. The excess entropy change on mixing at constant T and P 

d. The excess Helmholtz and Gibbs energy changes on mixing at constant T and P 

Transcribed Image Text:

P = RT V-b a V²