Study of Equilibria in Cadmium Bromide Complexes Solutions From the Aspect of Their Quantitative Determination

Abstract

The study of equilibria established in cadmium bromide complexes solutions was performed voltammetrically, by applying the linear sweep technique on the hanging mercury drop electrode, HMDE. In the studied systems the initial cadmium-ion concentration was equal, and the concentration of ligands, bromide ion, was gradually increased along with maintaining the pH-value and ion force of the solution at the constant values. The resulting shifts of the voltammogram peak reduction potential, which come as a result of the change in the electroactive species concentration due to the increase of the ligand concentration, were treated by the method of  DeFord-Hume. In this manner four cadmium bromide complexes species were detected and their stability constants were determined. All obtained stability constants matched the literature data in a satisfactory manner.