Conceptual change in an organic chemistry laboratory: A comparison of computer simulations and traditional laboratory experiments.

摘要

This quasi-experimental research study examined the effect of computer simulations and hands-on laboratory experiments in enhancing conceptual understanding and alleviating misconceptions of organic chemistry reaction mechanisms. Subjects were sixty-nine sophomore-level organic chemistry students enrolled in four laboratory sections. Laboratory sections were stratified across instructor and randomly assigned to serve as a control or treatment laboratory. Students in the control group performed all hands-on experiments. Students in the treatment group performed hands-on experiments for the first and last part of the semester but performed computer simulations for a five-week period in the middle of the semester. Prior to treatment, groups were equivalent with respect to academic orientation, motivation, formal reasoning ability, and spatial visualization ability.; Fifteen common misconceptions held by beginning organic chemistry students were identified from the Covalent Bonding and Structures Test. At the end of the semester, thirteen of these misconceptions persisted. Molecular geometry was the only category of misconceptions that significantly improved as a result of computer simulations, F(1,58) = 6.309, p = .015. No significant differential change was observed in misconceptions about bond polarity, molecular polarity, intermolecular forces, lattice structures, or the octet rule.; Computer simulations were found to result in significantly greater conceptual understanding of organic chemistry reactions on two of the experiments, Stereochemistry, F(1,55) = 6.174, p = .016, and Nucleophilic Substitution, F(1,57) = 6.093, p = .017. The other three experiments, Infrared Spectroscopy, Elimination, and Oxymercuration, did not show a significant differential effect between types of laboratory experiences. No significant differences were observed on long-term retention of concepts.; Overall conclusions from the study are that neither computer simulations nor hands-on laboratory experiments are effective in alleviating misconceptions, but that computer simulations can significantly improve conceptual understanding of organic reaction mechanisms.