Journal of the chemical society-faraday transactions vol:87 issue:8 pages:1075-1081
A kinetic study of the reaction Na + O2 + He k2 --> NaO2 + He has been carried out in a fast-flow reactor in the temperature and pressure ranges of, respectively, 392-777 K and 4-14 Torr. dagger Sodium atoms are generated either by thermal evaporation of sodium metal or by the technique of microwave-induced plasma afterglow atomization. Atomic absorption spectroscopy is used as the detection technique for atomic sodium. A fit of k2 to the expression A(T/300)n yields k2 = (8.6 +/- 0.7) x 10(-31) (T/300)-1.04 +/- 0.16 cm6 molecule-2 s-1. This rate expression will be compared with kinetic data derived for the above reaction on the basis of time-resolved flash photolysis and excimer laser photolysis measurements. Using the Troe formalism, values of k2 are calculated in the temperature range 200-2000 K and the importance of the reaction in the burnt-gas region of oxygen-rich flames is discussed.