The Fe E-pH Diagram

Accurate values of E for comparison with the values estimated from the diagram may be calculated from the Nernst equation as follows. The values 

Application of the equilibrium constant equation along with the value for [Fe+ ] and then the Nernst equation containing values for E and E° and the concentration changes (0.10 M for all other soluble species) will give accurate pH values for comparison with the estimates from the diagram. The estimated values from the diagram are again presented in brackets. 

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