Empirical extension using a term linear in ionic strength

2 Empirical extension using a term linear in ionic strength 

Experimental data shows conclusively that the extended Debye-Hiickel equation must be used for moderate and higher ionic strengths. 

There are two disposable parameters, a and b, in the Debye-Hiickel extended equation, and there are two ways to assign values to them. 

Often it is impossible to discriminate between these choices. This makes it very difficult to make any meaningful interpretations of specific values. 

Experimental values of b vary in magnitude and in sign from electrolyte to electrolyte, and as shown above depend on the value of Ba. Furthermore, it is impossible to split up these values of 

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