Leveraging understanding of energy from physics to overcome unproductive intuitions in chemistry

Electrostatic potential energy is a topic of great difficulty for many students. In this paper, we empirically test the utility of two approaches for laying a foundation for developing an understanding of energy in an electrostatic context, with interdisciplinary relevance. We examine student responses to a question about how the potential energy of a system of two attracting ions varies with distance (the “ions” task), and investigate how these responses change after students have been exposed to either a question designed to help them think about gravitational potential energy or the potential energy of a system of two attracting magnets. We found that performance on the ions task improved for those students who were prompted to think about the gravitational context, while it did not change for those who considered the magnets. The results are interpreted using dual-process theories of reasoning and decision making, and implications for instruction are discussed.

Figure 1

The ions question. Students were asked, “Which figure has a greater potential energy?” with answer choices “Figure a has a greater potential energy”; “Figure b has a greater potential energy”; “Both figures have the same potential energy”; and “Impossible to determine.”

Figure 2

The books question. Students were asked, “Which configuration, if either, has a greater potential energy?” with answer choices “The configuration with the book on the shelf at height C has greater potential energy”; “The configuration with the book on the shelf at height D has greater potential energy”; “Both configurations have the same potential energy”; and “Impossible to determine.”

Figure 3

The magnets question. Students were asked, “Between $t_1$ and $t_2$, does the potential energy of the two-magnets system increase, decrease, or remain the same?” with answer choices “Between $t_1$ and $t_2$, the potential energy increases”; “Between $t_1$ and $t_2$, the potential energy decreases”; “Between $t_1$ and $t_2$, the potential energy does not change”; and “Impossible to determine.”

Figure 4

Overview of the survey flow for the two versions addressed in this paper.

Figure 5

Overall performance of students on the combination of the initial and final ions questions, indicating how individual students changed their answers (or failed to do so) on each version of the survey.