We address the uniqueness and multiplicity of the equilibrium solutions in a specific class of chemically reactive system involving nonisothermal reactive gas absorption. A film model that is not restricted to a particular reaction regime is developed for (m,n)th-order irreversible reactions. Lower and upper bounds for the interfacial temperature rise are proposed, and tested by application to real systems, including the chlorination of n-decane, chlorination of toluene, and sulfonation of dodecylbenzene (DDB). We further develop a categorization of the possible bifurcation parameters, and propose lower and upper bounds for each of the new parameters in the generalized model. A parametric-sensitivity analysis in the kinetic- and reactor-parameter spaces is presented. It is shown that the steady-state multiplicity behavior of the system is more sensitive to the kinetic parameters, whereas a few of the new reactor parameters are of significant impact.