Isonitrosoacetophenone Thiosemicarbazone As An Analytical Reagent For Extraction And Spectrophotometric Determination Of Copper (II)

摘要

The present investigation deals with extractive Spectrophotometric determination of copper (II) by using isonitrosoacetophenone thiosemicarbazone (HINAPTSC). The method is based on instantaneous formation of a stable orange coloured complex with copper (II) at room temperature in the pH range 8.0 - 10.0, selectively extracted in ethyl acetate. The extracted species exhibits an absorption maximum at 500 nm where absorption due to reagent blank is negligible. The Beer's law is obeyed in the concentration range 0.2-6.0 μg/cm~3 with molar absorptivity 4.88 x 10~3 dm~3 mol~(-1) cm~(-1) of copper (II) with an optimum concentration range 1.0 - 6.0 μg/cm~3. The optimum extraction conditions have been evaluated by studying various parameters such as effect of pH, solvents, reagent concentration, time of equilibration and tolerance limit of the method towards various cations and anions usually associated with copper. The composition of the extracted species is determined by mole ratio method and verified by Job's continuation variation method. The Cu : HINAPTSC ratio is found to be 1 : 2. The proposed method is rapid, sensitive and reproducible and has been successfully used for the determination of traces of copper in synthetic mixtures, alloys and medicinal samples.