Polarographic studies on mixed Ligand complexes of cadmium-1-methyl imidazolemalonate system

ABSTRACT

The overall formation constants of the mixed ligand complexes of 1-methylimidazole [l-Melm] and malonate [Mal] with cadmium [II] have been studied polarographically at constant ionic strength, micro = 2. 0, [NaNO3] and pH 8 at 25 +/- 0.1 degree. The reduction of the complexes at a DME, is reversible and diffusion controlled. The constants for three mixed complexes of Cd[II] are log Beta11 = 4.0 for [Cd[l-Melm] [Mal]], log Beta12 = 4.4 for [Cd[l-Melm] [Mal]2] and log Beta21 =5.9 for [Cd[l-Melm]2 [Mal]]. The equilibrium constant values of the tendency of a ligand to add to a complex and to substitute another ligand were compared