The reaction chemistry was specified by the overall gas-phase heat of reaction (ΔH ovr ), species binding energies (BE A and BE B ), and the BEP relationship parameters (α and β). Vapor-phase flow reactors (CSTR) and batch reactors were modeled by systems of ordinary differential equations (ODEs) with two gas phase species, A and B, and two surface species, A*, B*, with open site *. Differential equations for the CSTR were as follows: