To explain the trend of an experimental dependence for concentration of chl
orine atoms in a discharge, the principal processes of the formation and de
cay in the plasma of a chlorine mixture with hydrogen were considered. The
rate coefficients and rates of processes involving electrons were calculate
d by mathematical modeling in order to reveal the contribution of each proc
ess to the observed concentration of chlorine atoms. The greatest contribut
ion is made by direct electron-impact dissociation. The experimental concen
tration of chlorine atoms at a high percentage of hydrogen is explained by
an increase in electron concentration and, hence, in the rate of the direct
dissociation process. It is suggested that chain reactions can make a subs
tantial contribution to the formation of atoms at low hydrogen concentratio
ns.