Halogens and Halogen-containing Derivatives

Chaffee, 1.1. Creaser, and J. O. Edwards, Inorg. Nuclear Chem. Letters, 1971, 7, 1. E. H. Appelman, Inorg. Chem., 1971,10, 1881. 

The kinetics and mechanism of the Cl -C103 reaction in moderately concentrated (2.5—5.8M) perchloric and sulphuric acid media have been studied, the overall reaction being represented by the equation 

The reaction order with respect to Cl falls from 2.0 at lower acidities to 1.1 at 5.6M-HCIO4. The order with respect to stoicheiometric acid concentration is high and may be accounted for by the reaction 

Chloride ion is found to have an accelerating effect on the reaction rate, and it is considered that if sufficient chloride ion is present the reaction 

Chlorine(i) species react with the tris-(l,10-phenanthroline)iron(n) ion in two ways, one of which is dependent on the dissociation of the complex cation and involves a one-electron oxidation to yield Fe(phen)3 + as product. The observed rate constant in conditions of excess oxidant may be described in terms of the expression 

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