2-Hydroxy-4-Ethoxy-5-Bromopropiophenone Oxime as an Analytical Reagent for Cu(II)

Abstract

2-Hydroxy-4-ethoxy-5-bromopropiophenone oxime (HEBPO)
was developed as a new analytical reagent for the gravimetric estimation
of Cu(II). In pH range 3 to 8 the reagent gives a buff coloured
precipitate with Cu²⁺. Job's method and Yoe Jones' mole ratio
method revealed that the stoichiometry of the complex is 1 : 2 metal
: ligand. The Beer law is obeyed up to 101.90 ppm of Cu²⁺. The
molar absorptivity and the Sandell's sensitivity at 420 nm were
found to be 1.725 X 10² Lit mol^-1 cm^-1 and 0.368  μg/cm2 respectively.
The stability constant of Cu(II)-HEBPO complex is found
to be 3.154 X 10⁸. Gibb's free energy change for complex formation
reaction was found to be -11.624 kcal/mole. The reagent can be
used for the analysis of brass.