Boron atom reactions. II. Rate constants with O2, SO2, CO2, and N2O

Abstract

The gas phase reactions of atomic boron with O₂, SO₂, CO₂, and N₂O have been studied using a new flow tube apparatus. Boron atoms were produced in a microwave discharge of a 0.02% mixture of diborane in argon. The bimolecular rate constants at 300 °K were obtained by measuring the density of boron down the flow tube as a function of reactant density. The rate constants for the O₂, SO₂, CO₂, and N₂O reactions are, in units of cm³ molecule⁻¹ sec⁻¹, 4.6±1.8×10⁻¹¹, 1.1±0.4×10⁻¹⁰, 7.0±2.8×10⁻¹⁴, and 2.1±0.8×10⁻¹⁴, respectively. These results are compared with the rates measured for the reactions of the group IIA and IVA atoms. The patterns observed in the data are noted and a possible mechanism is discussed.