An intermediate in the reaction between trans-aquabis(ethylenediamine) sulphitocobalt(III) and sulphite ion in aqueous solution

Abstract

At 25 °C. pH 7.1, and I= 1.00 mol dm^–3, the substitution reaction of trans-[Co(en)₂(OH₂)(SO₃)]⁺ by [SO₃]^2– proceeds via the O-bonded intermediate trans-[Co(en)₂(OSO₂)(SO₃)]^– as follows: [Co(en)₂(OH₂)(SO₃)]⁺+[SO₃]^2– [graphic omitted] {[Co(en)₂(OH₂)(SO₃)][SO₃]}^–, {[Co(en)₂(OH₂(SO₃)][SO₃]^– [graphic omitted] [Co(en)₂(OSO₂)(SO₃)]^–+ H₂O, [Co(en)₂(OSO₂)(SO₃)]^– [graphic omitted] [Co(en₂(SO₃)₂]^–, The values of K_IP, k₁′(lim.), and k₂ are 30 ±1 dm³ mol^–1, 20 ± s^–1, and 59 ± 7 s^–1.