New Analytical Technique for Determination of Trace Amount of Cu (II) by Using UV-Visible Spectrophotometric Method with Photometric Reagent.

3-nitrosalicylaldehyde thiosemicarbazone (3-NSTS) is proposed as a new photometric reagent for the extractive spectrophotometric determination of Cu (II). (3-NSTS) reacts with Cu (II) and form a stable coloured complex in the pH range 4.2 to 5.2. This was well extracted in n-butanol. The absorption spectrum of Cu (II) (3-NSTS) complex in n-butanol shows maximum absorbance at 420 nm. The system obeyed Beer’s law up to 2-8 µg / cm 3 . The molar extinction coefficient was found to be 1.9841 x 10 3 lit mol -1 cm -1 and the sensitivity of the method as defined by Sandell’s sensitivity was 3.2 x 10 -2 μg/cm 2 . The composition of the extracted species was determined by Job’s Continuous variation method, Mole ratio method and slope ratio method and it was found to be 1:1. The proposed reagent is satisfactorily applied for the determination of trace amount of Cu (II) from industrial waste water as well as synthetic and commercial samples.