Teacher trainees' interpretations of chemical stability and chemical reactivity

This paper reveals teacher trainees’ over-reliance on the octet model. It assesses the nature and possible origins of these conceptions. One hundred and thirty-eight teacher trainees in a teaching university, who were purposely selected, participated in this case study. Instruments used in gathering data were worksheets and focus group interviews. Data obtained were analysed quantitatively and qualitatively. Records of the interviews were transcribed after thematic descriptions. Findings showed that majority of the trainees relied heavily on the full shell concept model, which they imbibed from teachers, and so confused the chemical reactivity framework with that of chemical stability. This led them to pay attention to irrelevant features to the negligence of other authentic reasons in their assigned task. The octet model also led the trainees to reduce the relevant number of propositions that they could have considered as possibilities in differentiating between models. These findings will add to existing knowledge among the science learning community as they are relevant to educators interested in conceptual development and students’ learning progressions. Remediation was recommended to enable the trainees to form proper mental models of the concept of chemical stability and its application through innovative constructivist teaching strategies.