Science, Tech, Math › Science Texas Carbon Definition Can Carbon Form 5 Bonds? Share Flipboard Email Print Texas carbon refers to carbon atoms with five bonds. Todd Helmenstine Science Chemistry Basics Chemical Laws 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 January 10, 2020 A Texas carbon is the name given to a carbon atom that forms five bonds. The name Texas carbon comes from the shape formed by five bonds radiating outwards from the carbon similar to the star in the Texas state flag. Another popular idea is that the saying "Everything is bigger in Texas" applies to carbon atoms. Although carbon usually forms 4 chemical bonds, it's possible (though rare) for 5 bonds to form. The carbonium ion and superacid methanium (CH5+) is a gas that can be produced under low-temperature laboratory conditions. CH4 + H+ → CH5+ Other examples of Texas carbon compounds have been observed. Sources Akiba, Kin-ya et al. (2005). "Synthesis and Characterization of Stable Hypervalent Carbon Compounds (10-C-5) Bearing a 2,6-Bis(p-substituted phenyloxymethyl)benzene Ligand." J. Am. Chem. Soc. 127 (16), pp 5893–5901.Pei, Yong; An, Wei; Ito, Keigo; von Ragué Schleyer, Paul; Zeng, Xiao Cheng (2008). "Planar Pentacoordinate Carbon in CAl5+: A Global Minimum." J. Am. Chem. Soc., 2008 130 (31), 10394-10400.