Abstract
Crown ether-potassium ion complex extracts selectively copper-zincon anion complex as ion-pairs into chloroform phase in the presence of copper-zincon and zinc-zincon chelate anion, whereas quarternary ammonium ion extracts both anions. By measuring the absorbance of the chloroform phase at 615 nm, copper in the presence of zinc has been determined spectrophotometrically. The composition of extracted species was estimated to be Cu2+-zincon4−-(KL+)2.