Reactivity of chlorine atoms in aqueous solution Part 1The equilibrium ClMNsbd+Cl-Cl2-

Abstract

The equilibrium constant for reaction (1) has been determined in neutral solution to be (1.4±0.1)×10⁵ d mol^-1, with forward and reverse rate constants, k₁ and k_-1, of (8.5±0.7)×10⁹ d mol^-1 s^-1 and (6.0±0.5)×10⁴ s^-1, respectively. At 25°C the rate constants for the reactions of Cl^Nsbd and Cl₂^- were measured to be (2.5±0.3)×10⁵ s^-1 and (1.3±0.1)×10³ s^-1 with water and (6.5±0.6)×10⁸ d mol^-1 s^-1 and ca. 0, within experimental error, with 2-methyl-propan-2-ol. Deviation from the equilibrium values of [Cl^Nsbd] and [Cl₂^-] in the early stages of the reactions was investigated and shown to account for the discrepancy between the value of K₁ determined here and a previous estimate from our laboratory.