Abstracto
- The release of protons from Amberlite CG-50 ion-exchange resin into water at 25.0 ± 0.5 °C, induced by lithium, sodium, or potassium ions, is a first-order process with a rate constant of 7.4 ± 0.4 × 10-3 s-1. This constant is independent of metal-ion concentration and identity, quantity of resin, and stirring speed under the conditions employed. The rate constant for proton release into protium oxide exceeded that for deuteron release into deuterium oxide by factors of 3.06 ±0.17 (Na+) and 3.36 ± 0.38 (K+). The rate constant kn for lyon release into binary mixtures of protium oxide and deuterium oxide (atom fraction n of deuterium) is given by the equation kn = (7.4 ± 0.5 × 10-3 s-1)(1-n + [0.70 ± 0.02]n)3. The transition state for proton release from the resin appears to be that for migration of a preformed hydronium ion through the resin matrix. This migration generates a hole which is rapidly occupied by the metal ion.