The effect that comparing molecular animations of varying accuracy has on students’ submicroscopic explanations

Abstract

In this qualitative study, we examined how a group of seventeen first semester General Chemistry students responded when they were shown contrasting molecular animations of a reduction–oxidation (redox) reaction between solid copper and aqueous silver nitrate for which they first viewed a video of the actual experiment. The animations contrasted in that they portrayed different reaction mechanisms for the redox reaction. One animation was scientifically accurate and reflected an electron exchange mechanism, while the other was purposefully inaccurate and represented a physical exchange between the ions. Students were instructed to critique each animation for its fit with the experimental evidence and to ultimately choose the animation that they felt best depicted the molecular level of the chemical reaction. Analyses showed that most students identified that the electron exchange animation was the more scientifically accurate animation; however, approximately half of the students revised their drawings to fit with the inaccurate physical exchange animation. In addition, nearly all students thought that both animations were correct and useful for understanding salient information about the redox reaction. The results indicate that when students are shown contrasting animations of varying accuracy they make errors in deciding how the animations are supported and refuted by the evidence, but the treatment is effective. Contrasting animations promote students to think deeply about how animations fit with experimental evidence and is a promising way to engage students to think deeply about animations.