Extractive Spectrophotometric Determination of Cu(II) with 4-Chloron Isonitroso Acetophenone Thiosemicarbazone

Abstract

A method is proposed for the extraction and spectrophotometric
determination of Cu(II) at microgram levels by using 4-chloro
isonitroso acetophenone thiosemicarbazone (CINAPT) as an analytical
reagent. Cu(ll) forms reddish complex with CINAPT which
can be extracted in chloroform in the pH range 7.5 to 8.5 under
optimum conditions. The chloroform extract shows maximum
absorbance at 400 nm wavelength.
Beer's law is obeyed over the range of 0.2 to 20 microgram per
mL of Cu(II). The molar absorptivity is 2.518 x 10³ L
mol^-1 cm^-1. The composition of the species is found to have 1: 2
(metal : ligand) stoichiometry.
Interference due to diverse cations and anions has been investigated.
The method has been applied for the determination of copper
in alloys and pharmaceutical samples.