CITRATE COMPLEX OF CADMIUM

The citrate complexes of cadmium have been studied by pH titration method. Three complexes, one neutral (C) and two anionic (C_l^- and \(C_2^{2-}\)) containing one citrate ligand per atom of cadmium, have been found to be formed. The equilibrium constant of the reactions \(Cd_{2+} + H_3Cit \rightleftharpoons C+ 2H^+ (I) C\rightleftharpoons C_1^-+H^+ (II) \) (II) and \(C_1^- \rightleftharpoons C_2^{2-} + H^+\) (III) are respectively 6.43 X 10^-7, 1.59 x 10^-5 and 4.36 x 10^-9. The hydroxyl group of the citrate ligand reacts but the proton is not liberated. The probable structures f the complexes C, C₁^- and C₂^2- have been discussed.