Students' Use of Magnetic Models to Learn Hydrogen Bonding and the Formation of Snowflakes

Magnetic molecular models help students explore molecular structures and interactions. In this study, we investigated how pairs of students used magnetic models to explore hydrogen bonding and the 6-fold symmetry of snowflakes. Fourteen first-year students enrolled in a chemistry unit participated in pairs. Students' interactions with the magnetic models and their peers were video recorded and later transcribed. Students' hand-drawn diagrams, verbal explanations, and gestures were used to evaluate students' conceptual understanding. Students showed distinctly different patterns of interaction depending on their prior knowledge of hydrogen bonding and how they socially interacted. Pairs with alternative prior understanding of hydrogen bonding relied on prompts while using magnetic models to feel the attraction and repulsion between two water molecules. They then constructed a tetrahedral structure and discussed its similarities with the branches of snowflakes. Pairs with a better understanding of hydrogen bonding interacted more with each other, used magnetic models to create ring structures, and explained their similarities with the 6-fold symmetry of snowflakes. Despite gaining a new understanding of hydrogen bonding, most student pairs' explanations did not extend to the massive 3D expansion of molecular structures to form a snowflake. Educators should consider the affordances of magnetic models and students' group dynamics when teaching molecular interactions to explain macroscopic-level phenomena.