Environmental Media Phase-Tracking Units in the Classroom

Abstract

When teaching phase partitioning concepts for solutes in porous media, and other multi-phase environmental systems, explicitly tracking the environmental media phase with which a substance of interest (501) is associated can enhance the students' understanding of the fundamental concepts and derivations. It is common to explicitly track the customary mass, length, and time based units. The expansion described here is to also track the specific media phases to which these fundamental units apply. This additional step forces students to think more carefully about concentrations and other terms. This paper presents a consistent system of notation for teaching these concepts and some examples of how this system is used. The examples presented here are based on solid-liquid partitioning and a linear Freundlich adsorption isotherm, but could also be applied to other environmental media, such as air and biological tissue, as well as other partitioning models. This approach is most appropriate for advanced undergraduate and graduate students.