Using a pulse-radiolysis transient UV-VIS absorption system, rate constants for the reactions of F atoms with CH₃CHO (1) and CH₃CO radicals with O₂ (2) and NO (3) at 295 K and 1000 mbar total pressure of SF₆ was determined to be k₁ = (1.4 ± 0.2) × 10^-10, k₂ = (4.4 ± 0.7) × 10^-12, and k₃ = (2.4 ± 0.7) × 10^-11 cm³ molecule^-1 s^-1. By monitoring the formation of CH₃C(O)O₂ radicals (A > 250nm) and NO₂ (A = 400.5nm) following radiolysis of SF₆/CH₃CHO/O₂ and SF₆/CH₃CHO/O₂/NO mixtures, respectively, it was deduced that reaction of F atoms with CH₃CHO gives (65 ± 9)% CH₃CO and (35 ± 9)% HC(O)CH₂ radicals. Finally, the data obtained here suggest that decomposition of HC(O)CH₂O radicals via C - C bond scission occurs at a rate of <4.7 × 10⁵ S^-1.