  Teaching about energy in interdisciplinary settings that emphasize coherence
among physics, chemistry, and biology leads to a more central role for chemical
bond energy. We argue that an interdisciplinary approach to chemical energy
leads to modeling chemical bonds in terms of negative energy. While recent work
on ontological metaphors for energy has emphasized the affordances of the
substance ontology, this ontology is problematic in the context of negative
energy. Instead, we apply a dynamic ontologies perspective to argue that
blending the substance and location ontologies for energy can be effective in
reasoning about negative energy in the context of reasoning about chemical
bonds. We present data from an introductory physics for the life sciences
(IPLS) course in which both experts and students successfully use this blended
ontology. Blending these ontologies is most successful when the substance and
location ontologies are combined such that each is strategically utilized in
reasoning about particular aspects of energetic processes.
