THE ELECTRODEPOSIT ION BEHAVIOR OF TRACES OF

By means of radioactivity, the extent of silver deposition on platinum cathodes was determined at various potentials under conditions closely approaching equilibrium. For any specific solution having a concentration of silver of 10- ~ M or greater, the resulting curve agreed well with the polar-ographic curve. For concentrations equal to or smaller than 10-7)5, the amount of silver was insufficient to cover the lectrode and the resulting deposition curves often shifted to a potential several tenths of a volt more "noble " than that predicted by the Nernst equation. The shift, which may be the result of alloy formation, was influenced greatly by the "inert" electrode material. Changes in the electrode area and in the volume of solution were found to shift the position of the deposition curve in accordance with predictions based upon the Nernst equation. Complexing agents decreased and some-times eliminated the shift toward noble behavior whereas, in one case, a higher concentration of acid produced a larger shift toward "nobility.&quot