Determination of proton affinities from the kinetics of proton transfer reactions. VII. The proton affinities of O2, H2, Kr, O, N2, Xe, CO2, CH4, N2O, and CO

Abstract

The flowing afterglow and selected ion flow tube techniques are applied in a room temperature study of the kinetics of proton-transfer reactions of the type XH++Y?YH++X for X or Y=He, H2, O2, Kr, O, N2, Xe, CO2, CH4, CD4, N2O, OH, and CO, and for the deuteration of O2 by D3+. Equilibrium constants are determined and changes in thermodynamic state properties (ΔG°, ΔH°, ΔS°) are derived for the reactions with X/Y=H2/O2, O2/Kr, H2/Kr, H2/N2, O/N2, N2/Xe, Xe/CO2, CO2/CH4, CH4/N2O, and N2O/CO. Proton affinities are reported for O2, H2, Kr, O, N2, Xe, CO2, CH4, N2O, and CO, together with the heats of formation of their protonated species. Also a correlation is presented between the kinetic and thermodynamic results obtained in this study.