### Abstract

The kinetics of the unimolecular decomposition of the 1-chloroethyl radical have been studied. The reaction was isolated for quantitative study in a heated tubular flow reactor coupled to a photoionization mass spectrometer. Rate constants for the decomposition were obtained in time-resolved experiments as a function of temperature (848-980 K) and bath gas density (3-22×10^{16} molecule cm^{-3}) in He, Ar, and N_{2}. The rate constants are in the falloff under the conditions of the experiments. The falloff behavior was analyzed using a Master Equation analysis. A transition state model was created to obtain values of the microcanonical rate constants, k(E), needed to solve the Master Equation. The transition state model provides the high-pressure limit rate constants for the decomposition reaction (k_{1}^{∞} (CH_{3}CHCl→CH_{2}CHCl+H)=1.94×10^{9} T^{1.22} exp(-19,510 K/T) s^{-1}) and the reverse reaction (k_{-1}^{∞} (H+CH_{2}CHCl→CH_{3}CHCl)=3.35×10^{-14} T^{0.86} exp(-75.3 K/T) cm^{3} molecule^{-1} s^{-1}). Values of {ΔE}_{down} for the energy loss probability were obtained for each experiment using the exponential-down model. The values of {ΔE}_{down} display a pronounced positive temperature dependence with average values of 255 (He), 360 (Ar), and 261 (N_{2}) cm^{-1}. Parametrization of the temperature and pressure dependence of the unimolecular rate constant for the temperature range 298-1500 K and pressures 0.001-10 atmospheres is provided using the modified Lindemann-Hinshelwood expression.

Original language | English |
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Pages (from-to) | 817-824 |

Number of pages | 8 |

Journal | Symposium (International) on Combustion |

Volume | 25 |

Issue number | 1 |

DOIs | |

Publication status | Published - 1994 |

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### ASJC Scopus subject areas

- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology
- Mechanical Engineering
- Physical and Theoretical Chemistry
- Fluid Flow and Transfer Processes

### Cite this

*Symposium (International) on Combustion*,

*25*(1), 817-824. https://doi.org/10.1016/S0082-0784(06)80715-0