2-Chloro-2'Hydroxy-4'-Ethoxychalcone Oxime as an Analytical Reagent for Copper(II)

Abstract

2-Chloro-2'-hydroxy-4' -ethoxychalcone oxime (CHECOX) has
been prepared and used for the gravimetric and spectrophotometric
determination of copper(II) at pH 6.0-6.5. Job's method of continuous
variation and Yoe and Jones mole ratio method show metal-ligand
ratio in the complex to be 1 : 2. The molar absorptivity of
the complex at 400 nm is found to be 1.4912 X 10⁴ L.
mole^-1 cm^-1 . The stability constant determined spectrophotometrically
is found to be 2.72 X 10⁶ and Gibb's free energy change for
complex formation reaction is calculated to be 8.83 kcal/mole. The
Beer's law is obeyed upto 20 ppm of Cu(II) ion at 400 nm.