Effect of Electrode Configuration and Transition Time in Solid Electrode Chronopotentiometry

Abstract

▶ To determine the optimum electrode and transition time range for chronopotentiometric analysis, the transition time constant, i0τ1/2/C°, was measured for the reduction of silver(l) and lead(II), and the oxidation of iodide and hydroquinone, over a transition time range of 0.001 to 300 seconds. The transition time constant increased at long transition times, due to spherical contributions to diffusion and natural convection. Increase at short transition times was ascribed to charging of the double layer, electrode oxidation, and roughness of the electrode. By employing a horizontal electrode, with a glass mantle, oriented so that density gradients were not produced, i0τ1/2/C°, was maintained constant to ±0.2% with transition times of 7 to 145 seconds. © 1961, American Chemical Society. All rights reserved.