Nonequilibrium Contributions to the Rate of Reactions. II. Isolated Multicomponent Systems

Abstract

The nonequilibrium rates of reaction in multicomponent reactive systems are obtained by solving the Champman–Enskog equation. A Sonine polynomial expansion is used for the solution and its convergence is demonstrated for a wide range of system variables. It is found that the perturbation of the velocity distribution function for each reactive component depends on the deviation of the reactive collision frequency R(0)(cγ) from a special form R̄(0)(cγ). A model reactive system was examined with line-of-centers reactive cross sections and hard-sphere elastic cross sections chosen to fit the available data for the reaction H2+Cl=HCl+H. The deviation of the ratio of the forward and reverse rate coefficients (kf / kr) from the equilibrium value (kf(0) / kr(0)) was shown to be much smaller than the experimental deviation; this suggests that translational nonequilibrium is not significant, but does not exclude vibrational effects which could be more important.