VOLTAMMETRIC DETERMINATION OF CR(III) IN PLATING BATHS CONTAINING CR(III) SALTS AS THE MAIN COMPONENT

The differential pulse single-sweep voltammetric technique with hangin g mercury drop electrode was used for the determination of Cr(III). Th e determination was carried out in 0.2 mol/l sodium acetate as support ing electrolyte. The reduction peak of Cr(III) was recorded at - 1.5 V vs. Ag/AgCl reference electrode. The relative standard deviation was 3% for Cr concentrations in the range of 0.4 mol/l. The determination of impurities (Cd, Cu, Pb and Zn) in fresh and overworked galvanic bat hs using anodic stripping voltammetry in the differential pulse mode i s also described.