Spectrophotometric studies of V [IV], Co [II], Ni [II], Cu [II] and Zn [II] complexes with 8- [o-hydroxyphenylazo] 7-hydroxy-4- methyl-coumarin

ABSTRACT

The complexes formed between 8-[o-hydroxyphenylazo] - 7 -hydroxy-4-methylcoumarin [I] and V [IV], Co [II], Ni [II], Cu [II] and Zn [II] were studied spectrophotometrically in solutions. The different complexes were characterized and their stoichiometric ratios were thoroughly investigated. Methods for the spectrophoto-metric determination of these metals and Spectrophotometric titration using EDTA were reported. The interference of several metal ions was reported