Specific adsorption of acetate ions at the mercury—lithium acetate (AQ) interface

Specific adsorption of acetate ions at the mercury—lithium acetate (aq) interface has been investigated using both differential capacity and electrocapillary measurements. Variation of charge due to surface excess of lithium ions (q⁺) and of charge due to specifically adsorbed acetate ions (q^?1 with electrode charge (q^M) have been discussed. Such discussion inferred superequivalent adsorption of acetate ions at all positive charges for concentrations of lithium acetate ≥0.20 M whereas Esin-Markov plots predicted the absence of specific adsorption; the prediction of Esin-Markov plots has been shown to be faulty under certain conditions. The plots of φ^M-2vsq^?1 at constant q^M for acetate ion resembled the corresponding plots for F^? and BF^?₄ ions; the slope of these plots is negative up to coverages corresponding to 0.20 M lithium acetate. The identification of the isotherm parameter, (?φ^M-2/?q^?1)_q^M with the reciprocal of inner layer capacity at constant charge (_^?1Cⁱ) has been questioned.