Equivalent conductance additivity rule

For low-molecular weak electrolytes the concentration dependence of conductance is more complex, as in addition to the interionic friction effect it is strongly influenced by the association-dissociation reactions taking place in the solutions. However, as these in general follow the mass action law and thus, in simpler cases, the van t Hoff dilution law, their conductivity behavior is predictable. As a rule their equivalent conductivity steeply increases on dilution due to the increased dissociation of the electrolyte. 

This is the flux expression for the combined processes. The transport parts of Equation 4.25 cannot be put in the simple format of a single overall MTC such Equations 4.16 and 4.20. In addition, it cannot be constructed by applying the Ohm s law rules of adding the appropriate conductance and resistances in series. Although the air-phase concentration, Ca and the equivalent soil-side, air-phase concentration, Cah, are present they appear in an atypical form. The complex algebra results... 

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