Gronwall-LaMer-Sandved extension

In the application of equation (69) an arbitrary value of a is chosen so as to give calculated activity coeflScients which agree with those derived by direct experiment the proper choice of a is made by a process of trial and error until a value is found that is satisfactory over a range of concentrations. There is no doubt that the Gronwall-LaMer-Sandved extension represents an important advance over the simple Debye-Hilckel treatment, for it frequently leads to more reasonable values of the mean ionic diameter. The validity of equation (69) has been tested by a variety of activity measurements and the results have been found satisfactory were it not for the tedious nature of the calculations it would probably be more widely used. 

Table II. Constants for the Third and Fifth Approximations of the Gronwall, LaMer and Sandved Extension of the Debye-Huckel Theory...

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