Extractive Spectrophotometric Determination of Cobalt(II) with benzildithiosemicarbazone

Abstract

  An extractive spectrophotometric method for the determination of cobalt(II) using benzildithiosemicarbazone is reported. The cobalt(II)-benzildithiosemicarbazone complex with a molar absorptivity of 7.329 x 10³ L mol^–1 cm^–1 and Sandell's sensitivity of
0.008044 μg/cm² obeys Beer's law in the range 1.0-8.0 ppm of
cobalt(II). The instability constant of the complex is determined.
The effect of various diverse ions in the determination of cobalt(II)
is studied. The method is successfully applied for the determination
of cobalt(II) in medicinal and beer samples and the results are
compared with atomic absorption spectrophotometer.