Example on Adsorbed-Ion Activity Coefficients

The equation employed to calculate the thermodynamic exchange constant (K ) from the Kv of Na+-Ca2+ exchange (see Reaction 4.38 for stoichiometry), for example, is as follows  

For the direction and the stoichiometry of the exchange reaction used in this text (Reaction 4.38), the equations for estimating adsorbed-ion activity coefficients according to Argersinger et al. (1950) are 

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