Pre-Service Science Teachers' Mental Models Regarding Dissolution and Precipitation Reactions

This study described pre-service secondary science teachers' mental models of dissolution and precipitation reactions. The study took place at a mid-sized master's granting public institution located in southeastern United States. The twelve participants were either juniors or seniors in the Bachelor of Science in Science Education program or first year students in the Master's of Arts in Teaching Science Education program. All had completed two semesters of general chemistry with final grades of C or better.;Participants were shown six videos---four showing ionic solids dissolving in water and two of precipitates forming from the combination of the previous four ionic solutions. After each video, participants completed a questionnaire consisting of multiple choice questions and tasks involving the writing of chemical equations and providing particulate level drawings of the observed chemical phenomenon. Each participant was interviewed individually to explain his/her answers and to allow the researcher to probe the individual's understanding of the dissolution process.;Although the study used a population not previously reported in the literature, results from this study matched previously reported findings for populations of high school students, college students, and pre-service elementary teachers. Participants demonstrated several common misconceptions related to the topics of dissolution and precipitation reactions. These misconceptions included dissolving is the same as melting, ionic solids react with the solvent (water) to form new compounds, and precipitation reactions result in the production of two chemical compounds. The study also discussed the level of consistency exhibited by individuals in their multiple representations and explanations of the same chemical phenomenon.