Threshold Concepts for the Concept of Chemical Equilibrium

P&A 117

AN EXPLORATORY STUDY TO IDENTIFY THE EQUILIBRIUM THRESHOLD CONCEPTS FOR STUDENTS IN CHEMISTRY EDUCATION

Re: Submission 1326

Abstract

The characteristic triplet nature of chemistry (macroscopic, submicroscopic, and symbolic) has long been a substantial part of research and discussion in chemistry education (Dumon & Mzoughi-Khadhraoui, 2014; Prilliman, 2014; Taber, 2013). The three levels are considered levels of thought (Johnstone, 2000) and students’ performance has been attributed to their ability to conceptualize chemistry entities, phenomena, and ideas based on these levels.

Chemical equilibrium is one of the more difficult concepts in general chemistry, due to its abstract nature and demanding mastery of a large number of subordinate concepts (Finley, Stewart, & Yarroch, 1982; Quilez, 2007; Quilez-Pardo & Solaz-Portoles, 1995;). Equilibrium is an important concept in chemistry, due to its abstract nature, and is essential in developing an understanding of other areas of chemistry such as acid/base/salt behaviour, solubility, and oxidation/reduction reactions (Allsop, R.T., & George, N.H., 1982; Banerjee, A.C., & Power, C.N., 1991; Voska & Heikkinen, 2000).

Many chemistry students do not understand the concept of chemical equilibrium very well as indicated by their inability to express and apply the rich and productive thinking that the concept entails. The students have not yet crossed the conceptual threshold that leads to the meaningful understanding of this concept (Talanquer, 2015). Mastering a threshold concept requires time, effort, and learning scaffolded to facilitate the construction and accessibility to a clearer concept. It is therefore necessary to discover and identify the underlying threshold concepts inherent in understanding chemical equilibria to inform how to best support students’ learning.

Keywords: chemical equilibrium, threshold concepts

References

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Voska, K.W., & Heikkinen, H.W. (2000). Identification and analysis of student conceptions used to solve chemical equilibrium problems. Journal of Research in Science Teaching, 37(2), 160-176.