Donnan Potential in a General Electrolyte

When a thick soft plate is immersed in a general electrolyte solution, the Donnan potential Tdon is given by setting the right-hand side of Eq. (4.6) (in which —d is replaced by —oo) to zero, that is, Tdon is given as a root of the following transcendental equation  

The relationship between Tdon y is obtained in the following way. Integrating Eqs. (4.5) and (4.6) gives 

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