Science, Tech, Math › Science What a Double Bond Means in Chemistry Share Flipboard Email Print Bacsica / 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 October 03, 2019 A double bond is a type of chemical bond in which two electron pairs are shared between two atoms. This type of bond involves four bonding electrons between atoms, rather than the usual two bonding electrons involved in a single bond. Because of the large number of electrons, double bonds tend to be reactive. Double bonds are shorter and stronger than single bonds.Double bonds are drawn as two parallel lines in chemical structure diagrams. The equal sign is used to indicate a double bond in a formula. Russian chemist Alexander Butlerov introduced double bonds in structural formulas in the mid-19th century. Examples Ethylene (C2H4) is a hydrocarbon with a double bond between the two carbon atoms. Other alkenes also contain double bonds. Double bonds are seen in imine (C=N), sulfoxides (S=O), and azo compounds (N=N).