Straight-chain hydrocarbons: A hydrocarbon in which all carbon atoms are sp 3 -hybridized is a member of the class of alkanes, designated by the suffix –ane. When a double bond is present, the suffix is -ene, and the compound is an alkene. When a triple bond is present, the suffix is –yne, and the compound is an alkyne. The root names indicating the number of carbon atoms in the longest continuous chain are derived from Greek or Latin, except for the first four members of the series. For a cyclic structure, the prefix cyclo- is inserted before the root. Table X gives some skeletons and names of hydrocarbons. Comparable names apply to larger systems.