The pulse-radiolysis technique has been employed to produce and study the kinetics of hydrated electrons in a quaternary micro emulsion (Sodium Lauryl Sulfate electrons vary smoothly as the water droplet sizes are changed. The bimolecular rate constants for the reaction of with different solutes have been determined. It has been observed that Ϫ e aq the measured bimolecular rate constants for the reaction of hydrated electrons with different solutes are indicative of the solubilization sites, the water core sizes, and the surrounding environment.