What are the typical issues or topics with which students have difficulty? How can students be taught to solve problems and think like a chemist?
Most students have developed alternate notions for ordinary, every day "chemistry" situations involving reactions, heat, temperature, phase changes, etc., based on their daily life experiences and previous schooling. These alternate frameworks come in two varieties: misconceptions about what actually happens, and alternative explanations of what happens. In the former case, the ideas are simply empirically wrong; in the latter situation, the notions may be internally consistent but contrary to chemists' accepted views. A lot of research has focused on conceptual difficulties with particular content topics; the paper by Nakhleh , reviews much of this work and discusses concepts such as: matter as a continuous medium, atoms and molecules, intermolecular forces, phase changes, chemical equations, chemical change, and equilibrium. Understanding of the particulate nature of matter is reviewed by Gabel et al. , and Nicoll , investigates how undergraduates develop molecular models.
Many of the misconceptions elicited in these references are adhered to by undergraduates at the start of (and at the end of!) traditional lecture-based chemistry classes. It has been found that students' conceptual (mis)understandings have a tremendous amount of inertia to change, and can persist even in beginning graduate students who had been chemistry majors [4, 5]. Traditional problem-solving practice does little to overcome these difficulties; the curriculum and instruction must focus on the importance of conceptual understanding if improvement is to be observed [6, 7]. Johnstone's model , for the nature of chemistry, involving macro, sub-micro and symbolic aspects, suggests that successful problem-solving requires mastery of all three. Work by Bodner [9, 10], spanning nearly 20 years, studying freshmen through to graduate students, and covering various chemistry domains (general, organic, inorganic and physical) indicates that successful problem-solving is linked to the number and kinds of mental models that students have. Results from studies of student problem-solving have led to the development of standardized tests, such as the Chemical Concepts Inventory and Conceptual Questions [11, 12], which can be used to gauge the level of student comprehension. Innovative methods of engaging students and assisting them to overcome problem-solving (and other) difficulties are discussed in Instructional Strategies, below.
References on Course Content and Problem Solving:
- Why Some Students Don't Learn Chemistry: Chemical Misconceptions , M.B. Nahkleh, J. Chem. Educ. 69, 191, 1992. Available here.
- Understanding the particulate nature of matter, D.L. Gabel, K.V. Samuel, D. Hunn, J. Chem. Educ. 64, 695, 1987. Available here.
- A Qualitative Investigation of Undergraduate Chemistry Students' Macroscopic Interpretations of the Submicroscopic Structures of Molecules , G. Nicoll, J. Chem. Educ. 80, 205, 2003. Available here.
- I have found you an argument: The conceptual knowledge of beginning chemistry graduate students , G.M. Bodner, J. Chem. Educ. 68, 385, 1991. Available here.
- Evaluating Student Understanding of Solution Chemistry through Microscopic Representations , K.J. Smith, P.A. Metz, J. Chem. Educ. 73, 233, 1996. Available here.
- Concept learning versus problem solving: Is there a difference?, S.C. Nurrenbern, M. Pickering, J. Chem. Educ. 64, 508, 1987. Available here.
- Introductory College Chemistry Students' Understanding of Stoichiometry: Connections between Conceptual and Computational Understandings and Instruction , N.G. Lederman, A.J. Wolfer, ERIC ED440856. Click on Full-Text Availability for complete document. Available here.