The diffusion of ferri- and ferrocyanide ions in sodium hydroxide solutions has been studied by means of a platinum rotating disk electrode. Results were obtained at variable concentrations an in the range of temperature between 24 and 40°C. The product Dɳ/T was approximately constant and independent of temperature in the range studied. The dependence of D on the total ionic strength is mainly due to the change of viscosity at large ionic concentration.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exactas