TEACHERS’ MISCONCEPTIONS ABOUT THE EFFECTS OF ADDITION OF MORE REACTANTS OR PRODUCTS ON CHEMICAL EQUILIBRIUM

Article

Abstract

The importance of research on misconceptions about chemical equilibrium is well recognized by educators, but in the past, researchers’ interest has centered on student misconceptions and has neglected teacher misconceptions. Focusing on the effects of adding more reactants or products on chemical equilibrium, this article discusses the various misconceptions held by high school teachers. A misconception test was administered to two samples of chemistry teachers in Nanjing, China. Of the 109 teachers who participated in the test, only one understood that adding more CS2 gas to the equilibrium system CS2(g) + 4H2(g) ⇌ CH4(g) + 2H2S(g) at constant pressure and temperature can shift the equilibrium to the reactant or product side, depending upon the amount of CS2 in the initial equilibrium system. Most of the teachers relied on Le Châtelier’s principle and thus made erroneous predictions. The misconception test also revealed that those teachers who managed to compute equilibrium constants had a limited conceptual understanding of chemical equilibrium. Implications of these findings for teacher education and chemistry curriculum development are discussed.

Key words

chemical equilibrium Le Châtelier’s principle teacher knowledge teacher misconceptions 

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Copyright information

© National Science Council, Taiwan 2009

Authors and Affiliations

  1. 1.Department of Curriculum and InstructionThe Chinese University of Hong KongSha TinHong Kong
  2. 2.School of Chemistry and Environmental ScienceNanjing Normal UniversityJiangsuChina

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