Temperature dependence of the rate constants for the third order reactions: O2++2O2=O4++O2 and O4++2O2=O6++O2

Abstract

The temperature dependence of the rate constants for the reactions: O2++2O2=O4++O2 (1), O4++2O2=O6++O2 (2), were measured in a pulsed electron beam mass spectrometer in the temperature range 80–300 °K. The values k1 = 2.6 × 10−30 and k2 = 7 × 10−32 cm6 molecule−2 · sec−1 were obtained for 300 °K. Both reactions were shown to be third order. The temperature dependence fitted the relationship k = const T−n; n = 3.2 for Reaction (1) and 5.1 for Reaction (2). The equilibrium constants K1 and K2 could be measured over most of the experimental range. Van't Hoff plots of the equilibrium constants led to an approximate confirmation of ΔH1 and ΔH2 determined earlier by Conway.