European Journal of Biomedical and Pharmaceutical Sciences

SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF COBALT (II) AND NICKEL (II) USING 5-BHMBHBH

Dr. B. Saritha* and Prof. T. Sreenivasulu Reddy

ABSTRACT

Co(II) and Ni(II) react with 5-Bromo-2-hydroxy-3-methoxybenzaldehyde-4hydroxybenzoichydrazone at pH 7.0 to give brown and yellow coloured water soluble complexes. Co(II) shows maximum absorbance at 416 nm while Ni (II) shows maximum absorbance at 440 nm. Hence, 416 nm at 440 nm were selected for carrying out a simultaneous spectrophotometric determination of Co(II) and Ni(II). The molar absorptivities for Ni (II) are 2.103 ± 0.001 ×104 lit mol-1 cm -1 and 0.173± 0.002 × 10 4 lit mol -1 cm -1 respectively at 440nm and 416 nm and similarly, for Co (II) they are 2.025 ± 0.001 ×104 lit mol-1 cm -1 and 1.84 ± 0.002 × 10 4 lit mol -1 cm -1 at 416 and 440 nm respectively Hence, simultaneous spectrophotometric determination of Co(II) and Ni (II) in synthetic mixtures carried out. The method developed is highly sensitive, selective, precise and rapid for the direct spectrophotometric determination of Co(II) and Ni(II). The method is applied for the determination of Co(II) and Ni(II) in alloy samples.

Keywords: Co (II), Ni(II), 5-BHMBHBH, Spectrophotometry, Simultaneous spectrophotometry.