The measurement of oxygen transit time from ring to disc of a rotating ring disc electrode was used to determine the diffusivity of oxygen. The solubility of oxygen under atmospheric pressure was deduced from measurement of the limiting current of oxygen reduction in a saturated solution. The density and the kinematic viscosity of the solutions were also measured. The correlations obtained were used to calculate the following properties of four water-acetic acid-sodium acetate solutions : density, kinematic viscosity, absolute viscosity, diffusivity and solubility of oxygen in a temperature range of 25-80 degrees C. The solutions had a 5 and 10% water content in weight and a sodium acetate concentration of 0.5 and 1 mol [kg (acid + water)](-1).