Kinetic determination of traces of manganese(II) by its catalytic effect on the autoxidation of 1,4-dihydroxy phthalimide dithiosemicarbazone

A kinetic method is described for the determination of trace amounts of manganese(II) based on its catalytic effect on the aerial oxidation of 1,4-dihydroxyphthalimide dithiosemicarbazone. The reaction is followed spectrophotometrically by measuring the rate of change in absorbance at 594 nm. The calibration graph (rate constant vs. manganese concentration) is linear in the range 10–90 ng Mn ml^-1. The preparation and properties of the reagent are described and the kinetic parameters of the reaction are reported. There are few interferences.