University students’ considerations of the usefulness of models of chemical bonding

Teaching of chemical bonding is generally done using several models, which represent chemical bonding in different ways. Out of eight models of a hydrogen molecule, most first-semester students at a Norwegian university (N = 200) prefer the octet (duet) model or the Lewis structure. As reliance on the octet rule is shown to be associated with several alternative conceptions, the popularity of the octet model could hinder future learning. Comparing students who prefer a model with students choosing another model as their favourite, the first group rates the model as more useful than the other does. When asked about what it means to them that a model is useful, students (N = 20) tend to mention how a model can increase their understanding, is useful for visualisation or conveys information. None of the students mentioned exams or grades. This focus on understanding could imply that the students have an intrinsic motivation to learn and understand chemistry, but it could also be caused by students being accustomed to models being introduced and used as teaching models, rather than scientific models.