SHORT COMMUNICATION MICROWAVE ASSISTED SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF COPPER USING LEUCOCRYSTAL VIOLET

ABSTRACT. A sensitive spectrophotometric method has been developed for the trace determination of copper using leucocrystal violet as chromogenic reagent. The proposed method is based on the reaction of copper(II) with potassium iodide in acid medium to liberate iodine, which oxidizes leucocrystal violet to crystal violet dye having absorption maximum at 590 nm. The reaction between copper and potassium iodide is accelerated by irradiating the mixture with microwave energy for 15 s at 480 W. Beer’s law is obeyed in the concentration range 0.004-- 0.04 µg mL-1. The molar absorptivity, Sandell’s sensitivity, detection limit and quantitation limit were found to be 1.47 x 10 6 L mo