Abstract: An effect is induced within a chemical system consisting of at least two substances having differing degrees of microwave transparency, by exposing the mixture to focused microwave energy having a generally uniform energy density level, and an energy density at a level exceeding the capacity of at least one of the substances to dissipate the energy as thermal energy. The treatment is carried out until the thermodynamic state of the system is in a non-equilibrium state. The rate at which the effect is carried out is substantially increased over that which would be expected under equilibrium thermodynamic conditions. The effect may consist of an exothermic or endothermic chemical reaction or a separation process including a volatilization process.