Abstract

SIMULTANEOUS DETERMINATION OF NI (II) AND CO (II) USING CINNAMALDEHYDE THIOSEMICARBAZONE BY FIRST ORDER DERIVATIVE SPECTROPHOTOMETRIC TECHNIQUE

D.Gopala Krishna* and Ch.Kethani Devi

Abstract

Cinnamaldehyde thiosemicarbazone (CMTSC) was used as chromogenic reagent for Simultaneous spectrophotometric determination of Ni (II) and Co (II) ions. The reagent (CMTSC) gives intense yellow colour water soluble complexes with Ni (II) and Co (II) in presence of micellar medium (Triton-X-100 (5%) at pH 9.0. The maximum absorbance was observed at max 440 and 400 nm for Ni (II) and Co (II) respectively. The molar absorptivity and sandell’s sensitivity for Ni (II) and Co (II) complexes are found to be 4.77x104, 4.70x104 L.mol-1.cm-1 and 0.0012, 0.0012 μg/cm2 respectively. The reagent (CMTSC) forms 1:1 [M:L] complexes with Ni (II) and Co (II) with stability constants 8.17x 105 and 10.10x106 respectively. The First order derivative spectrophotometric technique has been developed for the simultaneous determination of Ni (II) and Co (II) at max 460 and 420 nm. The present simultaneous method was used for the determination of micro amounts of Co (II) & Ni (II) in some alloy steels and soil samples.

Keywords: Co (II), Ni (II), CMTSC, Simultaneous Derivative spectrophotometry.