ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 20, Number 3
JKCSEZ 20(3)
June 20, 1976 

Equivalent conductances of ammonium salts such as NH4Cl, CH3NH3Cl, (CH3)2NH2Cl, (CH3)3NHCl and (CH3)4NCl have been measured in methanol-water mixtures of various composition (0.0∼0.6-mole frcation: m. f.) in the concentration range from 0.01 to 0.04 M at 25℃, and limiting equivalent conductances (Λ0) are determined by the analysis of Fuoss Onsager's semiempirical equation.The experimental results are discussed in terms of varing the size of Λ0 due to the salts species and solvent composition. It has been observed in quite common over all salts that Λ0 decreases with the increase of m. f. methanol, and the maximum decrement in Λ0 shows between water and 0.1 m. f., while the plot of Λ0 vs. m. f. goes through a minimum at 0.4 m. f. and then turns slightly upward. On the other hand, the Λ0 decrease with the increase of the size of ammonium cation and the larger values Λ0 are showed in comparison with those of values observed for the corresponding n-RNH3Cl under the same experimental procedure. All these behaviors are considered to be closely correlated with the structures of solvents and solutes and the significant similarities are compared with the behaviors of partial molar volumes for amine salts in same solvent system.