Margules Equations and Slightly Non-ideal, Symmetric Solutions

Margules Equations and Slightly Non-ideal, Symmetric Solutions 

The parameter Wq has units of energy and is independent of composition, but varies with T and P. It can be thought of as the energy necessary to interchange a 

By analogy with (15.22) we can now write the other excess functions for this symmetric slightly non-ideal solution as 

We have already seen that the excess properties relate to each other in exactly the same way as do the usual thermodynamic functions. The same thing now applies to the Marguies parameters, since they are simply another way of writing excess properties. Thus, as we showed with the excess functions, we can now write relations such as the fundamental equation (5.11) to interrelate Marguies parameters  

And all the other thermodynamic relations also apply, such as 

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