Activation Energies of the Proton‐exchange Reactions in Water Measured with the ¹H‐NMR Spin Echo Technique

Abstract

Abstract From the pH‐dependence of the transverse relaxation‐time T 2 of protons in 17 O‐enriched water we have determined the rate constants k 1 und k 2 of the two proton‐exchange processes (I) and (II) magnified image in the temperature range from +5°C to +60°C. – Modified Bloch equations including exchange between the different states of the proton‐septett are used to fit the experimental data yielding directly the rate constants k 1 and k 2 . Classical and quantum mechanical relations connecting the limiting ionic equivalent conductivities λ H+ and λ OH− with the rate constants k 1 and k 2 are discussed.