New Perspectives in Science Education

In the framework of conceptual change theories in the learning sciences, identification of pre- or misconceptions and their replacement by scientifically validated conceptions is a central aspect of any teaching [1]. Recent neuroscientific explorations brought new dimensions to the problem by showing the importance of inhibitory processes [2]. Physical chemistry at the undergraduate level is known for being a difficult topic, due to its abstract character and the need to combine physical insight with a mathematical toolkit. Entropy and the second law of thermodynamics is a central topic in the physical chemistry curriculum, upon which most STEM students step during their first year at university. Specific difficulties linked with these concepts include the existence of two possible approaches, a macroscopic and a molecular one, whose interconnections are seldom made explicit. In this study, we present and discuss results of misconception identification for first-year bachelor students in chemistry, pharmacy and geology in a French-speaking Belgian university, using a pre- and post-test about entropy and the second law, before and after a one-semester course using the most common macroscopic teaching method. The questions of this test have been developed based on a detailed analysis of the approaches of standard physical chemistry textbooks. In addition, the investigation of remaining misconceptions of more advanced students (2nd and 3rd bachelor year, 1st and 2nd master year) completed the study. Some of the identified misconceptions are comparable to those already published in the literature [e.g. 3], and new ones are detected. Some misconceptions are rather of ontological nature whereas other ones result from inappropriate interpretation of analogies. A typical example is the microscopic disorder metaphor, which is widely used to give some physical meaning to the entropy concept in an otherwise mostly macroscopic approach. Despite its popularity, this metaphor creates major cognitive conflicts in the problem-solving process as confirmed by our research. Our results indicate that most erroneous conceptions remained after the one-semester course and that some were even aggravated. They also have highlighted the need to deepen the meaning of entropy in the microscopic approach and the importance of establishing a conceptual link with the macroscopic approach in order to allow a more refined understanding of the very concept of state function.

Keywords: conceptual change, misconceptions, entropy, second law of thermodynamics.

References:

1. Amin, T. G.; Levrini, O. Converging Perspectives on Conceptual Change. Mapping an Emerging Paradigm in the Learning Sciences, Routledge (London, 2018)
2. Nenciovici, L., Allaire-Duquette, G., & Masson, S. (2019). Brain activations associated with scientific reasoning: a literature review. Cognitive Processing, 20(2), 139–161.
3. Bennett, J. M., & Sözbilir, M. (2009). A Study of Turkish Chemistry Undergraduates’ Understanding of Entropy. Journal of Chemical Education, 84(7), 1204.