The electrochemical processes of aqueous Br&-system on platimzed titanium were studied by the method of the rotating disk electrode. Both the cathodic and the anodic processes involve two consecutive electrochemical steps, comparably rate-controlling, cath I Brt + e z Br-+ Brada, f&II II oath II Brads + e _ Br-. aIlI R&m~&L.es processus &ctrochimiques du systeme Br,/Br-aqueux sur le titane platine ont 6ti: &udi& par la metbode de l%lectrode B disque tournant. Tant le m&anisme cathodique que celui anodique sont control&s par deux stades electrochimiques consecutifs oath I Br, + e z Br-+ Brad., IUIII cath II Brsds + e J_ Br-, Ml1 cin&iquemem d6terminants en pareille mesure. Zusammenfassung-Man untersuchte die Kinetik der elektrochemischen Reaktionen im System Br,/Br-an einer rotierenden Elektrode aus platiniertem Titan. Sowohl der kathodische wie such der anodische Vorgang setzt sich aus zwei aufeinanderfolgenden Schritten zusammen, welche ungefahr in gleichem Masse geschwindigkeitsbestimmend sind: kath I Br, + e 1 Br-+ Br,,,, *xl II kath II Brads + e -Br-.
-anl AMONG the halogen/halide systems, the electrochemical kinetics of the bromine/ bromide system has been stated to be more like that of the system Cl&!l-than that of I,/I-.1-s However, no extensive kinetic study on the bromine/bromide system has been published so far, and the aim of the present work is to determine the kinetic parameters and to elucidate the mechanism of the cathodic and anodic processes.
The rotating disk electrode was used for the present study because the bromine processes are markedly rapid, so that, using a stationary electrode, diffusion control intervenes and hinders the determination of kinetic parameters.