Science, Tech, Math › Science Divalent Cation Definition in Chemistry Share Flipboard Email Print A divalent cation is an ion with a 2+ valence. Carlos Febres-3D, 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 May 06, 2019 A divalent cation is an cation with valence of 2+. This type of ion may form two chemical bonds with anions. Also Known As: bivalent cation Examples A magnesium ion, Mg2+ is a divalent cation. In fact, all of the alkaline earth metals (group 2) form divalent cations. Source Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.