AbstractVinyl and isopropyl radicals were generated by the pyrolysis of azoisopropane in the presence of acrolein at 473–563 K. Reaction products were analyzed by gas chromatography. Rate constant ratiosk2/k1= 0.02 ± 0.01 andk4/k3= 0.01 ± 0.005 are suggested for the following reactions:The rate constant ratio of reactions (7) and (c) obeys the Arrhenius equation\documentclass{article}\pagestyle{empty}\begin{document}$$ k_7 /k_c^{1/2} = (1.02 \pm 0.7)10^7 \,{\rm exp[ - (28}{\rm .42} \pm {\rm 2}{\rm .97)kJ/}RT]\,{\rm dm}^{{\rm 3/2}} \,{\rm mol}^{{\rm - 1/2}} \,{\rm s}^{{\rm - 1/2}} $$\end{document}The Arrhenius equation was derived for (k8+