AN OUTLINE OF ENERGETICS IN RELATION TO THE MOVEMENT OF MATERIALS THROUGH A TWO-PHASED SOLUTION SYSTEM

Abstract

A concise equational analysis of the process of movement of solute and water through a 2-phased soln. system is presented. This particularly discusses the effects due to the presence of solute in soln. Comparison of discussions relating diffusional movement based on concn. differences with that based on free energies is made. This survey points up 2 situations: (1) where concn. differences between phases alone are concerned, a constituent component of solution will tend to move with the direction in which the concn. (or diffusion "pressure") of the species in question, decreases; (2) where other factors such as temp., pressure, or metabolism are or are not concerned also, a constituent component or soln. will tend to more through a 2-phased system with the direction in which the specific free energy of the species in question, decreases. In other words, under all conditions, the latter situation obtains. Since movements in natural systems include flux both with and against the direction in which the concn. of a particular constituent component in solution decreases, an energy intensity approach is to be preferred. It is necessary in any case where energy expenditures are to be evaluated, and where influences other than the mere presence of solute in soln. are involved, as in general in nature.