Reactions of Halate Ions

The kinetics and mechanisms of some reactions of aqueous bromite have been reported.In the reaction with iodide in alkaline solution, 

The hydroxide-ion dependent pathway probably reflects a reaction of bromous acid although thermodynamic data are not yet available for the ionization of this acid. The second route involves the reaction 

The reaction of chlorine dioxide and sulphur(iv) has been investigated in the pH range 8—13 (phosphate and borate buffers), where in the presence of a slight excess of (sulphite) the major products are chlorite and sulphate ions with only miorr amounts of chloride and chlorate formed. In the overall reaction, 

Formate ions are oxidized to carbonate by bromite 2 the overall reaction 

The rates of reaction (monitored by loss of BrV) show acceleration initially before slowing down, the catalytic agent being the CO32- produced. The mechanism proposed is written as 

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