Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 5 4 2005 10.5194/acpd-5-5167-2005 http://www.atmos-chem-phys-discuss.net/5/5167/2005/ http://www.atmos-chem-phys-discuss.net/5/5167/2005/acpd-5-5167-2005.html http://www.atmos-chem-phys-discuss.net/5/5167/2005/acpd-5-5167-2005.pdf 5167 5182 2005-07-22 Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes D. Rodríguez A. Rodríguez A. Notario A. Aranda Y. Díaz-de-Mera E. Marínez Facultad de CC Medio Ambiente, Universidad de Castilla La Mancha, Avenida Carlos III, s/n, 45071 Toledo, Spain Instituto de Tecnologías Química y Medioambiental (ITQUIMA), Universidad de Castilla La Mancha, Avenida Camilo José Cela, s/n, 13071, Ciudad Real, Spain Facultad de CC Químicas, Universidad de Castilla La Mancha, Avenida Camilo José Cela, no 10, 13071, Ciudad Real, Spain The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined, for the first time, the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1) were: trans-2-pentenal (1.31±0.19)×10−10; trans-2-hexenal (1.92±0.22)×10−10; trans-2-heptenal (2.40±0.29)×10−10; n-pentanal (2.56±0.27)×10−10; n-hexanal (2.88±0.37)×10−10; n-heptanal (3.00±0.34)×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.