Rates of OH radical reactions. VI. Reactions with C3H6, 1hyphen;C4H8and 1hyphen;C5H10at 297 K

摘要

Absolute rate constants, for the reactions of hydroxyl radicals with C3H6, 1hyphen;C4H8and 1hyphen;C5H10at 297plusmn;2 K, have been measured in the gas phase, using the flashhyphen;photolysis resonancehyphen;absorption technique and OH from the flashhyphen;photolysis of N2O/H2mixtures, lgr;gsim;200 nm. The rate constants in units of cm3molminus;1sminus;1were found to be:kC3H6=1.48plusmn;0.17times;1013,k1hyphen;C4H8=2.01plusmn;0.15times;1013, andk1hyphen;C5H10=2.39plusmn;0.23times;1013. The quoted errors are the 95percnt; confidence limits. The approximate concentration of free radicals formed in the system has been determined in separate experiments. The maximum effect of secondary reactions of these radicals on the measured rates has been discussed and assessed to be less than 10percnt;.