Non-Extractive Spectrophotometric Determination of cu (Ii) Using 2-Hydroxy-3-Methoxy Benzaldehyde Thiosemicarbazone (Hmbatsc)

A highly sensitive and selective spectrophotometric method was developed for the determination of trace amount of copper (II) in aqueous DMF medium. The copper ion forms a light green colored complex with 2-Hydroxy-3-Methoxy benzaldehyde thiosemicarbazone (HMBATSC) in an acidic buffer of pH 5.0. The complex has an absorbance maximum at 395nm, was stable for more than 48 hours. The complex shows maximum absorbance at 395nm. Beer's law is obeyed in the range 0.254- 2.542 μgml -1 . The molar absorptivity and sandell's sensitivity of the proposed method were found as 6.0 x 10 3 L.mol -1 cm -1 and 0.011μgcm -2 respectively. The light green colored complex has 1:1 (Cu (II) - HMBATSC) Stoichiometry .The stability constant of the complex was determined as 12.306 x10 5 by Job's method. A sensitive and selective second order derivative spectrophotometry has also been proposed for the determination of Cu (II). The interference of various cations and anions were studied. The developed methods were successfully employed in the determination of Cu (II) in water and real samples. Keywords: HMBATSC, Determination of Cu(II), Spectrophotometry.