The data pf dosspcoatopm cpmstamts for aliphatic amines and quaternary ammonium-methylorange salts are based on the electrosatic theory of conductance. Dissociation constants for primary amines nad quaternary ammonium-methylorange salts (1$ imes$10$^{-5}$~1$ imes$10$^{-3}$ M) in nitrobenzene solution or water solution was evaluated from the relation of the concentration and the electric conduction and the electric conductance at $25^{circ}C$ Plots of ${delta}C$ against reciprocal conductance were linear ; hence the center-to-center distance of this salt was 1.75 $AA$ in nitrobenzene solution.