Association in ternary systems

We shall only give detailed consideration to the simplest case where we have a dilute solution of A and S in a solvent B and where the only complexes formed are between A and S. 

We shall now test this equation by reference to several systems containing ethyl alcohol (A), carbon tetrachloride (B) and a third component (S) which is capable of forming complexes with the alcohol. 

If we consider solutions very dilute in alcohol and containing an excess of the active solute S then the alcohol will be present either as monomer or as AS complexes. Furthermore since cannot be greater than c, it can be neglected in comparison with so that (26.94) can be written approximately 

For a series of solutions with constant, a graph of against should be linear through the origin with a slope 1/(1 +iTcC ). 

This prediction has been confirmed by a spectroscopic examination of systems of this kind. Figs. 26.11 and 26.12 show the results for 

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