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The role of the steric factors in the electrode reactions occurring on the interface covered by aliphatic alcohols and acids has been investigated, taking as an example the Cd 2+ /Cd(Hg) system. It has been shown that this process takes place inside the inner layer and the activated complex is created by the replacement of r ≠ water molecules from the surface. From studies carried out at surfactant concentrations corresponding to the plateau of the adsorption isotherm the steric factors r ≠ / r i have been determined ( r i is the number of solvent molecules replaced from the surface by one molecule of adsorbed surfactant). By comparison with investigations performed at lower coverages the magnitude of r ≠ and r i has been estimated. The influence of different factors on the experimental value of these parameters has been discussed.

The mechanism of Cd2+ discharge and cadmium amalgam dissolution in the absence and presence of organic neutral surfactants is compared. The generality of the stepwise mechanism of this reaction occurring on Hg electrode both covered and non-covered by the surfactants is shown. The reliability of the existence of Cd+ as an intermediate in the electrode reaction is discussed.