This study identified and quantified chemistry conceptions students use when solving chemical equilibrium problems requiring application of Le Chatelier's principle, and explored the feasibility of designing a paper and pencil test to accomplish these purposes. A 10-item pencil and paper, two-tier diagnostic instrument, the Test to Identify Student Conceptualizations (TISC), was developed and administered to 95 second-semester university general chemistry students after they received regular course instruction concerning equilibrium in homogeneous aqueous, heterogeneous aqueous, and homogeneous gaseous systems. To validate TISC, nine students from a stratified random sample were selected for interviews incorporating comparable chemistry problems. The probability that TISC correctly identified an answer given by a student in the interview was p ϭ .64, whereas the probability that TISC correctly identified a reason given by a student in the interview was p ϭ .49. Eleven prevalent incorrect student conceptions about chemical equilibrium were identified by TISC. Students consistently selected correct answers more frequently (53% of the time) than they provided correct reasons (33% of the time). The level of association between student answers and their respective reasons on each TISC item was quantified using conditional probabilities calculated from logistic regression coefficients. The Kuder-Richardson 20 reliability for TISC was .79.
This study explores general-chemistry instructors' awareness of and ability to identify and address common student learning obstacles in chemical equilibrium. Reported instructor strategies directed at remediating student alternate conceptions were investigated and compared with successful, literaturebased conceptual change methods. Fifty-two volunteer general chemistry instructors from 50 U.S. colleges and universities completed an interactive web-based instrument consisting of open-ended questions, a rating scale, classroom scenarios, and a demographic form. Survey respondents who provided responses or described remediation strategies requiring further clarification were identified (n ¼ 6); these respondents amplified their views in separate, researcher-led semistructured phone interviews. All 52 responding chemistry instructors reported and identified common student areas of difficulty in chemical equilibrium. They reported employing a variety of strategies to address and attempt to remediate students' alternate conceptions; however, these self-reported strategies rarely included all four necessary conditions specified by Posner, Strike, Hewson, and Gertzog (Science Education, 66, 211-217, 1982) to stimulate conceptual change. Instructor-identified student alternate conceptions were congruent with literature-reported alternate conceptions of chemical equilibrium, thus providing validation support for these compilations. Implications for teaching and further research are also highlighted. ß
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.