The purpose of this study was to describe the effect of multiple knowledge representations of physical and chemical changes on the development of primary pre-service teachers' cognitive structures. The study took place in an introductory general chemistry laboratory course in a four-year teacher education program. Multiple knowledge…

Students' mental models of diffusion in a gas phase solution were studied through the use of the Structure and Motion of Matter (SAMM) survey. This survey permits identification of categories of ways students think about the structure of the gaseous solute and solvent, the origin of motion of gas particles, and trajectories of solute particles in…