Solutions in acetone. Part I. Conductances in anhydrous acetone of some perchlorates, perchloric acid, and lithium chloride at 25 °C by a four-electrode alternating current potentiometric method

Abstract

The preparation of acetone with an extremely low moisture content (0·001%) has been achieved, and the product shown to be stable to self-condensation for several months. Conductances of LiClO₄, NaClO₄, KClO₄, NH₄ClO₄, LiCl, and anhydrous HClO₄ have been measured in anhydrous acetone by a four-electrode a.c. potentiometric method which incorporates the advantages of using alternating current and yet completely eliminates errors due to end effects, polarization, and the presence of finely divided platinum. The respective limiting equivalent conductances and dissociation constants (10⁴K_D) found from Fuoss plots are: 197·8, 5·9; 201·0, 15·6; 189·6, 32·6; 229·9, 74·3; 193·7, 0·028; and 214·1, 6·9. The results indicate that although anion solvation effects are apparent, cation solvation is generally greater than anion solvation in acetone, and the low dissociation constant of LiCl is in accordance with the general tendency of such chlorides to be weak electrolytes in differentiating solvents. The need for transference data in acetone is indicated. The findings indicate that the potentiometric method should generally be applicable to electrolyte solutions in all solvents and can be used with advantage in all cases influenced by the errors mentioned above.