A Rate - Catalyzed Reversible Reduction Of Sb(III) at the D.M.E. Induced by Trace Thiosulfate in HCLO₄: A Comparison with Bromide

Abstract

Alternating current polarography was employed to compare qualitatively the rate-enhancing properties of several electronically polarizable anions (including the halides) on the irreversible reduction of Sb(III) in HCLO₄.In terms of the concentration required to produce one-half the maximum a.c. peak current for the reversible process it was found that added Na₂S₂0₃ in 0.75M HCLO₄ surpassed the halides by several orders of magnitude and that only micromolar levels of Na₂S₂0₃ are required to yield sharp, undistorted a.c. polarographic peaks and nernstian d.c. waves at −0.109 volt vs S.C.E. Millimolar levels of NaBr on the other hand were required to produce peaks of comparable height at −0.104 volt vs. S.C.E.

Key Words:

• Sb(III), A. C. Polarography
• Catalyzed
• Trace Thiosulfate