Aerosol-OT and some other surfactant molecules form reverse micelles in an organic phase in contact with an aqueous salt solution. Experimental data of the distribution of cations in Aerosol-OT-isooctane-water-salt systems have been measured at 23 degrees C for different chloride salts. The effect of different variables on the equilibrium ion distribution between the organic phase, containing reverse micelles, and an aqueous phase, containing different salts, has been formulated in terms of dimensionless groups. These variables are (i) the initial surfactant concentration, (ii) the nature and initial salt concentration of each salt, and (iii) the initial volume ratio of the two phases. The model distinguishes between different ions via the equilibrium constants of their ion exchange reactions with the surfactant counterion. It accurately predicts the distribution of single charge and multicharge ions between the two phases of the system. A model formulated in dimensionless form, with few independent dimensionless groups rather than many independent variables, has definite advantages for the treatment of complex systems. In this work, the predictions of the model are compared with experimental results and with the predictions of other phenomenological models published in the literature for reverse micellar systems.