In this study, first the level of interconnectedness of the key concepts concerning the topic of physical and chemical changes in pre-service chemistry teachers' (PSCTs') semantic memories was explored. Second, the group cognitive structures of the PSCTs that contain associations between these key concepts and the response concepts that appeared…

Compares the effects on the knowledge structure of the learners of using two different Mindtools--semantic networks and rule-based expert systems--for representing the content of a course. Results showed that students in the semantic network class possessed more hierarchical knowledge structures than the other group. (Contains 29 references.) (JLB)