Spectrophotometric Study of Stability Constants of Fe (III), Co (II) and Cu (II) Complexes of Salicylhydroxamic Acid at Room Temperatures

Complexation of Fe (III), Co (II), Cu (II) with salicylhydroxamic acid have been studied spectrophotometrically at absorption maximum for Fe - hydroxamate, Co- hydroxamate, and Cu- hydroxamate, of 520, 510 and 640nm respectively. The complexations were carried out at temperatures 25?C at the wavelengths of the respective complexes. The stoichiometry of the complexes were determined using Job?s continuous variation method and the value was found to be 1:2 metal to ligand ratio for Fe (III) and Co (II) and 1:1 for Cu (II). Stability constants (K) values were calculated using the continuous variation method and found to be in the order 5.9 x 103, 5.2 x 103 and 1.4 x 103 for Fe - hydroxamate, Co- hydroxamate, and Cu- hydroxamate respectively.