Hexane is a hydrocarbon with the chemical formula C6H14; that is, an alkane with six carbon atoms. The term may refer to any of four other structural isomers with that formula, or to a mixture of them.In the IUPAC nomenclature, however, hexane is the unbranched isomer (n-hexane); the other four structures are named as methylated derivatives of pentane and butane. IUPAC also uses the term as the root of many compounds with a linear six-carbon backbone, such as 2-methylhexane C7H16, which is also called isoheptane.