EXTRACTIVE SPECTROPHOTOMETRIC ETERMINATION OF RHODIUM (III) USING 2-(5- BROMO-2- OXOINDOLIN-3-YLIDENE) HYDRAZINECARBOTHIOAMIDE AS AN ANALYTICAL REAGENT

Borgave S. S. and Barhate V. D.*

ABSTRACT

2-(5- bromo-2- oxoindolin-3-ylidene) hydrazine carbothioamide, [5-Bromoisatin thiosemicarbazone (HBITSC)] extracts Rhodium (III) quantitatively (99.20%) into n-amyl alcohol. The n-amyl alcohol extract shows an intense peak at 495nm (λ max). Beer’s law is obeyed over the Rh (III) concentration range 1.0 – 6.0ug/ml. The molar absorptivity is 3345 dm3 mole-1cm-1 at 495 nm and Sandel’s sensitivity is 30.76 ng/cm2. The composition of extracted species found to be 1:3 (Rh: HBITSC) by Job’s continuous variation and Mole ratio method. Interference by various ions has been studied. The proposed method has been applied for the determination of Rh (III) in synthetic sample.

Keywords: HBITSC, Iridium, Spectrophotometry, Molar Absorptivity.