AbstractMathematical solutions for the polarographic current as a function of time are given for the case of two‐step electrode reactions: R → Ra → P (R: radicals produced homogeneously in solution by a short pulse of high energy electrons; Ra: radical adsorbed at the electrode; P: product of oxidation or reduction). If R is long‐lived or disappears according to first order kinetics, the differential equations involved are amenable to solution. If R disappears by second order kinetics, an explicit solution cannot be given; the solution for first order disappearance, however, may well be applied to such cases at times shorter than the first half‐life time of the radical. The current‐time curves exhibit a maximum whose magnitude and position with respect to time can be expressed in terms of the ratioV=k/k1wherekis the transfer rate constant in s−1and k1the time constant of the disappearance of the radicals in the solution, k1is measured by recording the optical absorption of the radicals as a function of time.The current‐time curves obtained for the oxidation of the ethanol radical at a mercury electrode are described by the above two‐step electrode reaction,kis obtained at different electrode potentials. The transfer coefficient for the oxidation of the ethanol radical