Dissociation of Halogens in Shock Waves

Abstract

The rate of dissociation of Cl₂ has been measured at high temperatures in a shock tube. The temperature dependence curves, regardless of Cl₂ concentration, are fitted by invoking 4° of freedom of internal motion and an activation energy of 48 kcal. From the temperature T_H at which the decrease of Cl₂ optical density through dissociation matches the increase due to the cooling, by reaction enthalpy, the dissociation energy of Cl₂ has been calculated. The agreement with the well‐known spectroscopic value gives a confirmation of the shock‐tube temperature measurements and of many assumptions made in the other calculations.