Reaction of oxygen atoms with carbonyl compounds. Part 1.—Formaldehyde

Abstract

The reaction between excess atomic oxygen and formaldehyde in the gas phase has been studied in a flow system at 300 K using product analysis, e.p.r. and chemiluminescence. The initial step O + H₂CO→HCO + OH (1) has a rate coefficient of (9.0 ± 1.0)× 10¹⁰ cm³ mol^–1 s^–1. By comparing the reaction products with those of the reaction of oxygen atoms with ethylene where the initial steps are O + C₂H₄→CH₃+ HCO (12), O + CH₃→H₂CO + H (13) it is shown that the relative rate constants of the subsequent reactions O + HCO→OH + CO (8), O + HCO→H + CO₂(9), H + HCO → H₂+ CO (14) are in the ratio k₈ : k₉ : k₁₄= 0.54 : 0.46 : 4.0.