The peroxodisulphate–hexacyanoferrate(II) reaction. Reactivity and ionic association in isodielectric water–co-solvent mixtures

Abstract

The association constants of the potassium peroxodisulphate ion pair (KS₂O₈^–) and the potassium hexacyanoferrate(II) ion pair [KFe(CN)₆^3–] and the rate constant between peroxodisulphate and hexacyanoferrate(II) ions have been measured in several water–co-solvent mixtures. The assumption of ionic association does not provide a satisfactory interpretation of the experimental results.