A linearization principle for the stability of the chemical equilibrium of a binary mixture

We consider the stability of a chemical equilibrium of a thermally conducting two component reactive viscous mixture which is situated in a horizontal layer heated from below and experiencing a catalyzed chemical reaction at the bottom plate. We provide a method for an easy derivation of the nonlinear stability bound, derived explicitely in terms of the involved physical parameters. It enables us to derive a linearization principle in a large sense, i.e. to prove that the linear and nonlinear stability bounds are equal.