Science, Tech, Math › Science Decomposition Reaction Definition Share Flipboard Email Print In a decomposition reaction, one reactant yields two or more products. Adrianna Williams/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. Anne Marie Helmenstine, Ph.D. Facebook Twitter 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. Learn about our Editorial Process Updated on January 12, 2019 A decomposition reaction is a type of chemical reaction in which one reactant yields two or more products. The general form for a decomposition reaction is: AB → A + B Decomposition reactions are also known as analysis reactions or chemical breakdowns. The opposite of this type of reaction is a synthesis, in which simpler reactants combine to form a more complex product. You can recognize this type of reaction by looking for a single reactant with multiple products. In certain circumstances, decomposition reactions are undesirable. However, they are intentionally caused and analyzed in mass spectrometry, gravimetric analysis, and thermogravimetric analysis. Decomposition Reaction Examples Water can be separated by electrolysis into hydrogen gas and oxygen gas through a decomposition reaction: 2 HAnother example of this type of reaction is the spontaneous decomposition of hydrogen peroxide into water and oxygen: 2 HThe decomposition of potassium chlorate into potassium chloride and oxygen is yet another example: 2 KClO Cite this Article Format mla apa chicago Your Citation Helmenstine, Anne Marie, Ph.D. "Decomposition Reaction Definition." ThoughtCo, Apr. 5, 2023, thoughtco.com/definition-of-decomposition-reaction-604995. Helmenstine, Anne Marie, Ph.D. (2023, April 5). Decomposition Reaction Definition. Retrieved from https://www.thoughtco.com/definition-of-decomposition-reaction-604995 Helmenstine, Anne Marie, Ph.D. "Decomposition Reaction Definition." ThoughtCo. https://www.thoughtco.com/definition-of-decomposition-reaction-604995 (accessed June 7, 2023). copy citation