Learning Chemistry Using Multiple External Representations

Abstract

This chapter focuses on how students used various multiple visual and auditory external representations to develop their understanding of limiting reagents. They used the Synchronized Multiple Visualizations of Chemistry (SMV Chem) program. SMV Chem allowed learners to use five external representations of a given chemistry topic in any order or combination that they chose. The four visual external representations consisted of a real time video of a chemical reaction (macroscopic level of understanding), a computer animation of the reaction (microscopic level), a graphical representation (symbolic level), and a text representation of a mathematical problem concerning limiting reagents. Each visual external representation had an accompanying audio track to narrate the action that occurred during the representation. The audio track could be selected or not, according to the users choice. The module demonstrated the limiting reagents concept with a vinegar and baking soda reaction. We chose this module because the topic of limiting reagents provided students with many opportunities to explore the macroscopic, microscopic, symbolic, and mathematical levels in developing their understanding of the chemistry. Specifically we sought to identify the representations that were useful and then the particular characteristics that made those representations effective in helping students create their understanding.