Abstract

SPECTROPHOTOMETRIC STUDIES OF SOME TRANSITION ELEMENTS AS COMPLEXES WITH NEW AZODYE 2- (SULFAPYRIDINE AZO)-4,5-DIPHENYL IMIDAZOLE

Asaad A. Ali, Montha. Kh. H. and Tarek A. Fahad*

Abstract

The yellow (λmax 440nm.) azodye ligand 2-(Sulfapyridine azo )-4,5- Diphenyl Imidazole (L) forms a stable red (λmax 480nm.), orange (λmax 480nm.) and red-violet (μmax 500nm.) color complexes with divalent cations cobalt, nickel and copper respectively, with stoichiometry of all 1:2 ( M:L ). The complexes were characterized by FT-IR, M.P., visible, molar conductivity and atomic absorption spectroscopic. The suitable pH values for forming complexes are 11, 9 and 12 respectively. With molar absorptivity coefficients 4.2, 3.5 and 3.0 104 l.mole-1.cm-1 respectively. And obeyness of Beer‟s law up to 8.1 ppm of Co, 8.1 ppm of Ni and 7.6 ppm of Cu. The optimum conditions of the formation of complexes were investigated and their stability formation constants were determined by using of corresponding solutions method. The chemical formula of their complexes were suggested.

Keywords: Sulfapyridine, Azodyes, Corresponding solutions method, Formation constant, Stoichiometery, Complexes and Spectral studies, Molar conductivity