Condensaton of a supersaturated vapor. IV. The homogeneous nucleation of binary mixtures

Abstract

The upward thermal diffusion cloud chamber was used to measure the supersaturations (i.e., activities) required for the homogeneous nucleation of two binary mixtures, o‐xylene–m‐xylene and ethanol–water. These measurements were compared to the predictions of the classical theory of homogeneous nucleation. Good agreement was found for o‐xylene–m‐xylene at all compositions and for alcohol rich mixtures of ethanol and water. However, at high water concentrations, much more alcohol was required than is predicted by theory. The lack of equilibrium surface enrichment of the nuclei was postulated as the reason.