Using electrostatic potential maps as visual representations to promote better understanding of chemical bonding

Abstract

Static visual representations (VRs) of chemical structures are necessary for an understanding of chemical bonding, a topic which continues to lead to learning difficulties and misconceptions for many students. The efficacy and problems associated with the use of VRs of chemical structures and chemical bonding in the form of electrostatic potential maps resulting from accurate quantum mechanical calculations are the subject of this study, which involved a sample of first year, second semester students, studying the elective course "Science Education"(N = 31). Students distinguished between nonpolar and polar covalent bonding, however, they encountered difficulties with concepts related to ionic bonding. Most students did not employ multistructural thinking (in the sense of the SOLO taxonomy), when providing explanations about the variation of bond polarity. Persistence of a covalent-ionic bond dichotomy was apparent, while for some, ions can be involved in both ionic and covalent bonding. Many students preferred to use their established high school knowledge. On a positive note, many students were clearly affected by the information provided by the colored VRs. Finally, the minimal experience of our students with these VRs leads us to believe that a more systematic and extensive coverage would be likely to produce improved outcomes.