Words or Pictures: A comparison of written and pictorial explanations of physical and chemical equilibria

Abstract

The features of a concept or principle an individual chooses to highlight in an explanation or description may be related to the medium of communication used. Different aspects of understanding can be revealed through words and through drawings. This two-part exploratory study examined the differences between explanations of physical and chemical equilibria generated by means of words or pictures. Participants included both instructors and students, who were randomly assigned to provide either written explanations or drawings of physical or chemical equilibrium at the macroscopic and particulate levels. For both studies, analyses revealed that significantly different features appeared in the written and pictorial explanations of equilibrium. The written responses focused more on processes such as the dynamic nature of equilibrium, whereas pictorial representations highlighted structural aspects of equilibrium, such as the spatial arrangement of molecules. Regardless of the level of chemistry knowledge, people conveyed the same type of information via the use of different representations and visual tools.

Keywords:

• Explanations
• Drawings
• Representations
• Equilibrium
• Chemistry

Acknowledgements

The authors would like to acknowledge support from the National Science Foundation (NSF) award number REC-0440103, Design Principles for Effective Molecular Animations. They would also like to thank Barbara Tversky for taking the time to introduce them to cognitive science research strategies and for her encouragement and many helpful suggestions. Gratitude is also due to Roy Tasker, Jerry Honts, Jerry Suits, David Falvo, David Pringle, Robin Macaluso, Heng-Yu Ku, Dilek Ardac, and the University of Northern Colorado Chemical Education Research Group for their willingness to review and comment on all aspects of this study.