Exciting teaching and learning when multiple models are used to explain chemistry ideas

This case study describes the multiple models used to teach chemical equilibrium and examines the teacher’s reasons for using models. Three consecutive Grade-12 lessons were studied and the teacher presented the ‘school dance’, the ‘sugar in a teacup’, the ‘pot of curry’, and the ‘busy highway’ analogical models. The data yielded the following outcomes: The teacher used the students’ prior knowledge wherever possible and responded to student questions with exciting stories and analogies. He planned to discuss where each analogy broke down but did not. Students enjoyed the teaching but built variable mental models of equilibrium and female students disliked some masculine analogies and other students did not recognize all the taught processes. Most students learned that equilibrium reactions are dynamic, occur in closed systems and the forward and reverse reactions are balanced.