In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond between two carbon atoms. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula C_nH_2n-2. Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C₂H₂, known formally as ethyne using IUPAC nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic but tend to be more reactive.