Polarographic Behavior of Manganese(II) in the Presence of Oxalate Ions in Perchlorate and Sulfate Solutions

Abstract

The dc polarographic method has been applied to study coordination equilibria between Mn(II) and oxalate ions in perchlorate and sulfate solutions. The stoichiometries of complexes formed in solution and those reduced at a dropping mercury electrode were established. The stability constants of the Mn(II) oxalate and sulfate complexes, as well as their diffusion coefficients, were determined at a constant ionic strength 0.5 mol·L −1 and 25°C. The stabilities of these Mn(II) complexes were compared with the corresponding complexes of other divalent metal ions. The polarographic method was able to identify complexes that have not been established by other methods and to determine their stability constants with high accuracy.

Effect of gluconate ions on electroreduction phenomena during manganese deposition on glassy carbon in acidic chloride and sulfate solutions

“…Similar values are expected in the sulfate baths, but these could not be calculated unfailingly, since the Levich equation was not obeyed unambiguously. Obtained results are in a good agreement with the literature data, where Mn(II) diffusion coefficients of order 10 À6 cm 2 /s in the chloride and sulfate solutions of pH 2-6 were reported [27][28][29]. Fig.…”