Adsorption on a Surface Fraction Basis

Considering that surface coverage by a metal (-SM) is given in units of 0 (see box above), and 1-0 represents the uncovered surface (-S) (see Equation E), then based on Equation F and the pH-dependent surface electrical potential, j/ (Equation 4.27), 

Taking logs on both sides of Equation 4.31 and considering a metal cation with valence 2 gives 

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