Science, Tech, Math › Science Chemical Energy Definition and Examples What Is Chemical Energy? Share Flipboard Email Print Vitelle / Getty Images Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated August 05, 2019 Chemical energy is the energy contained in the internal structure of an atom or molecule. It is a measure of a substance's capacity to transform into another substance via a chemical reaction. This energy could be in the electronic structure of a single atom or in the bonds between atoms in a molecule. Chemical energy is converted into other forms of energy by chemical reactions. Examples of substances that contain chemical energy include: WoodFoodGasolineBatteries Chemical energy is released or absorbed as chemical bonds are broken and reform. It is a misconception that a substance always releases more energy than it absorbs! Chemical energy is calculated as the difference between the energy of the products and reactants. This may be measured using a calorimeter or calculated based on the bond energies of the chemical bonds. Reference Schmidt-Rohr, K (2015). "Why Combustions Are Always Exothermic, Yielding About 418 kJ per Mole of O2". J. Chem. Educ. 92: 2094–2099.