Binary nucleation. I. Theory applied to water–ethanol vapors

Abstract

A quantitative study of nucleation in vapor mixtures of ethanol and water near 273 °C is presented. First, Reiss’ theory of binary nucleation is reexamined. The theory is modified slightly in order to yield the proper limit for homogeneous nucleation in a one-component system. Moreover, a corrected expression for the equilibrium concentration of mixed clusters is derived. Calculations of the critical vapor activities needed to produce a visible condensate are presented and compared with the results of Flood’s cloud chamber experiments. The agreement is only fair, but qualitative accord is found.