ABSTRACT
The hypothesis of internally mixed aerosol is broadly used to analyze the evolution of the atmospheric aerosols. This seems to be physically plausible, and furthermore it is the only possible characterization of the aerosols until more advanced instruments for measuring the aerosol composition have been developed. Expanding upon a previous article, in which the evolution of a generally mixed aerosol is obtained under condensation-evaporation, we are able to analyze the goodness of the internally mixed aerosol assumption with regard to this phenomenon. We have obtained the result that this is a valid assumption.