Research into practice: Using molecular representations as a learning strategy in chemistry

Abstract

Research in chemical education over the last 20 years has revealed that many students have unacceptable, incomplete or non-existent mental models of chemical substances and processes at the molecular level. Multimedia resources produced in the VisChem project (see http://vischem.cadre.com.au/) have been designed to address this problem. This paper investigates the effectiveness of VisChem molecular-level animations in enhancing student’ images of substances and processes in first year university chemistry. The effectiveness of these animations, and the way they were presented, were evaluated using a pre- and post-test format, with follow-up interviews of selected students. The pre- and post-test showed the sophistication and scientific acceptability of students’ images of molecular and ionic substances, before and after instruction. A comparison of pre- and post-data reveals significant improvements in students’ mental models of these chemical phenomena. In addition to this, data on self-perceptions of students’ confidence in their responses, and the vividness of their images, reveal a significant increase in both aspects following instruction. Interviews were used to probe what students believed to be the main sources of any changes in imagery or confidence. Without prompting, the molecular-level animations were commonly identified as a contributing factor.