The Structure of Surface Complexation Models

It is possible to distill from the discussion in Secs. 5.1 to 5.5 a set of general properties for surface complexation models. These properties 

CONSTRAINT EQUATIONS. FoT each class of reactive surface hydroxyl groups, there is an equation of mole balance. This equation has the general mathematical form 

For each of the surface charge densities oh, ois and o-os an equation that includes the relevant surface complexes can be established. The surface density of net proton charge is given by the expression 

This equation and Eq. 5.82 provide the mass and charge balance constraints on any surface complexation model. 

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