Kinetics of homogeneous binary condensation at the stage of formation of the bulk of the liquid phase

The second stage of homogeneous binary condensation is considered. It is during this stage, following the stage of nucleation, that the bulk of the liquid phase is formed. A kinetic theory of homogeneous binary condensation at this stage is developed. Taking into account the depletion of the initial vapor mixture, transcendental equations are found which determine the time dependence both of composition of droplets and of activities of vapor mixture components. The problem of finding the spectrum of linear sizes of droplets is reduced to the solution of analogous problem in the kinetics of homogeneous unary condensation and is solved with the help of iteration procedure. A quantitative definition of the concepts of the “first” and “second” stages of binary condensation is given, and the estimates for the durations of these stages are obtained. The duration of the first stage (usually called “nucleation”) is important to correctly calculate experimental nucleation rates. As shown by numerical evaluations, the use of the first stage duration instead of the duration of the “nucleation pulse” in calculating experimental nucleation rates can, under some circumstances, improve their agreement with predictions of the classical nucleation theory.