The reactions of alkoxy radicals with O 2 . II. n ‐C 3 H 7 O radicals

n ‐C 3 H 7 ONO was photolyzed with 366 nm radiation at −26, −3, 23, 55, 88, and 120°C in a static system in the presence of NO, O 2 , and N 2 . The quantum yields of C 2 H 5 CHO, C 2 H 5 ONO, and CH 3 CHO were measured as a function of reaction conditions. The primary photochemical act isand it proceeds with a quantum yield ϕ 1 = 0.38 ± 0.04 independent of temperature. The n ‐C 3 H 7 O radicals can react with NO by two routesThe n ‐C 3 H 7 O radical can decompose viaor react with O 2 viaValues of k 4 / k 2 ≃ k 4b / k 2 were determined to be (2.0 ± 0.2) × 10 14 , (3.1 ± 0.6) × 10 14 , and (1.4 ± 0.1) × 10 15 molec/cm 3 at 55, 88, and 120°C, respectively, at 150‐torr total pressure of N 2 . Values of k 6 / k 2 were determined from −26 to 88°C. They fit the Arrhenius expression:\documentclass{article}\pagestyle{empty}\begin{document}$$ \log (k_6 /k_2) = - 2.17 \pm 0.20 - (879 \pm 117)/2.303{\rm T}{\rm .} $$\end{document}For k 2 ≃ 4.4 × 10 −11 cm 3 /s, k 6 becomes (2.9 ± 1.7) × 10 −13 exp{−(879 ± 117)/T} cm 3 /s. The reaction scheme also provides k 4b / k 6 = 1.58 × 10 18 molec/cm 3 at 120°C and k 8a / k 8 = 0.56 ± 0.24 independent of temperature, where