pentene
/ˈpɛntiːn/Chemistry
noun
Each of a number of isomeric liquid alkenes with the formula C5H10; especially either of the straight-chain isomers CH2CH(CH2)2CH3 (1-pentene) or CH3CHCH(CH2)CH3 (2-pentene).
Origin
Late 19th century; earliest use found in Philosophical Transactions of the Royal Society of London. From penta- + -ene.