title: The trouble with chemical energy: why understanding bond energies requires an interdisciplinary systems approach.
abstract: Helping students understand "chemical energy" is notoriously difficult. Many hold inconsistent ideas about what energy is, how and why it changes during the course of a chemical reaction, and how these changes are related to bond energies and reaction dynamics. There are (at least) three major sources for this problem: 1) the way biologists talk about chemical energy (which is also the way we talk about energy in everyday life); 2) the macroscopic approach to energy concepts that is common in physics and physical sciences; and 3) the failure of chemistry courses to explicitly link molecular with macroscopic energy ideas. From a constructivist perspective, it is unlikely that students can, without a coherent understanding of such a central concept, attain a robust and accurate understanding of new concepts. However, changes are on the horizon, guided by the increasing understanding that difficult concepts require coherent, well-designed learning progressions and the new National Research Council Framework for K-12 Science Education. We provide supporting evidence for our assertions and suggestions for an interdisciplinary learning progression designed to better approach the concept of bond energies, a first step in an understanding chemical energy and behavior of reaction systems that is central to biological systems.
authors.affiliation: Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA. mmc@msu.edu
authors.forename: Melanie M
authors.initials: MM
authors.lastname: Cooper
authors.forename: Michael W
authors.initials: MW
authors.lastname: Klymkowsky
mesh_terms: D055598:Chemical Phenomena; D003198:Computer Simulation; D003479:Curriculum; D006801:Humans; D058025:Interdisciplinary Studies; D059032:Learning Curve; D013816:Thermodynamics