Micro determination of Cadmium (II) and Mercury(II) with New Reagent 5-[(4- hydroxyl phenyl)azo ] -4,6- di hydroxyl -2- mercapto pyrimidine as a chelating Reagent by spectrophotometric methods.

Abstract

A simple, accurate and sensitive spectrophotometric method for the determination of
cadmium (II) and mercury (II) is described. The method is based on the chelation of Cd (II)
and Hg (II) ions with 5-[(4-hydroxy phenyl)azo]-4,6 dihydroxy-2- mercapto pyrimidine
(HADMP) to form an intense colour soluble products, that are stable and have a maximum
absorption at 573.5 nm and at 585 nm. The molar extinction coefficient (ε) 1.5×104 and
2.4×104 L.mole-1.Cm-1 for Cd (II) and Hg (II) respectively .The stability constant, relative
error and standard deviations for Cd (II) and Hg (II) were, 2.02×108, 1.05×108 L.mole-1 and
(2%, 1.176%), (2%, 2%) respectively. The new reagent and the two metal complexes have
been prepared in aqueous solutions and were characterized by electronic spectrum, F.T.IR
and also molar conductivity. Under optimum conditions the described methods were applied
satisfactorily to biological sample.