Insights Obtained Through the Study of a Concentration Cell

Although students may be able to use equations to generate numerical data, they often are unclear about the significance of their results. Students have difficulty connecting phenomena observed in the macroscopic world with corresponding mathematical descriptions and consistent interpretations in terms of the behavior of atomic entities. This paper describes a way to help students gain insight into the relationship between measured cell potentials and the concentration of ions in solutions, through the use of a thought experiment involving a concentration cell. The process points to the need to make the distinction between a mathematical description of a phenomenon and a reasonable physical interpretation.