Applying the Systematic Treatment of Equilibrium

The systematic treatment of equilibrium is best understood by studying some examples. 

The dissociation of water into H+ and OH occurs in every aqueous solution  

Step 2 Chaise balance. The only ions are H+ and OH, so the chaise balance is 

Step 3 Mass balance. Reaction 8-13 creates one H for each OH-. The mass balance is simply H 11 = [OH ], which is the same as the charge balance for this system. 

This is the only step in which activity coefficients enter the problem. 

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