Spectrophotometric and coulometric titration investigations of oxidation states and forms of ruthenium(IV) in hydrochloric acid solutions

The complicated chemical equilibria among oxidation states and forms of ruthenium exist in HCl solutions owing to hydration, hydrolysis, polymerization and redox reactions. Species of ruthenium compounds in HCl solutions are studied by Spectrophotometric and electrogenerated CuCln(n − 1)− coulometric titration methods. This work provides evidence for some ruthenium complexes and a theoretical basis for the coulometric determination of ruthenium.