Potentiometric Studies of Binary Complexes of Transition Metal Ions with Lauric Acid

Abstract

The potentials of binary complexes of the Lauric acid ligand with various biologically vital divalent metal ions such as Mn(II), Co(II), Ni(II), Cu(II)and Zn(II) have been studied in 50% DMSO-water mixture at constant ionic strength by Bjerrum method. Hydrogen ion concentrations were measured and the formation of binary complexes was inferred from the corresponding potentiometric pH-titration curves. The metal to ligand mole ratio was maintained at 1:5 to facilitate the maximum number of ligands to the metal ion. The dissociation constant has been determined by the half-integral method and pointwise method and were found in good agreement with each other. The Metal-Lauric acid stability constants have been calculated and compared with the results.