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

Journal of Solution Chemistry (Impact Factor: 1.18). 02/2011; 40(2):247-260. DOI: 10.1007/s10953-011-9649-7


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 0.5mol⋅L−1 and25 °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.

KeywordsPolarography–Manganese(II) complexes–Oxalate complexes–Stability constants–Electrode reduction mechanism

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Available from: Jadwiga Urbańska, May 03, 2014
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