FIELD: chemistry.
SUBSTANCE: method of determining rhodium (III) in aqueous solutions by the method of inversion voltammetry according to selective electrooxidation peaks of lead (II) from intermetallic compounds Rh3Pb2 and Rh5Pb7 is that rhodium is precipitated on the surface of the graphite electrode together with lead, forming an alloy in the presence of platinum (IV, II), palladium (II) and gold (III) ions in Rh: Pt=1:1 ratios, Rh: Pd=1:10, Rh: Au=1:10, the accumulation of rhodium ions on a graphite electrode in a stirred solution in the presence of lead ions is carried out for 180-240 seconds at an electrolysis potential minus 1.5 V from the background electrolyte 1M HCl with subsequent registration of anodic peaks of selective lead electrooxidation from alloy with rhodium at a potential sweep rate of 0.05-0.06 V/s, and the concentration of rhodium ions is determined from the area under the peaks of selective electrooxidation of lead in the potential range from -0.5 to -0.2 V, using the method of additives of certified mixtures.
EFFECT: determination of rhodium ions in aqueous solutions by inversion voltammetry in the presence of platinum, palladium, and gold ions.
2 tbl, 2 dwg, 1 ex
