AN ULTRASONIC STUDY OF SOME OF THE COMPLEXING REACTIONS OF CHLORIDE WITH CADMIUM ION

The ultrasonic absorptions of 0.25 M aqueous solutions of cadmium ions, containing various amounts of hydrochloric acid, have been measured by a pulse technique between 13 and 143 Mc/second at 16°, 25°, and 35 °C. A relaxation occurs in this region, and it has been interpreted in terms of the interacting association reactions[Formula: see text]An ultrasonic determination of the equilibrium quotient of the second of these reactions has been made, and the association and dissociation rate constants are reported for both reactions. In addition, the volume changes, ΔV, in the two reactions have been estimated, along with the activation energy for the dissociation of CdCl3−. The analysis breaks down at low ligand concentrations, and this is ascribed to the influence of a third interacting reaction.