|Acetylene Dibromide||Acetylene Dichloride||Acetyleneurea||Acetylleucine Monoethanolamine||Acetylpheneturide|
|UN number||1001 (dissolved)
3138 (in mixture with ethylene and propylene)
|Jmol-3D images||Image 1|
|Molar mass||26.04 g mol−1|
|Density||1.097 g/L = 1.097 kg/m3|
|Melting point||−80.8 °C; −113.4 °F; 192.3 K (Triple point at 1.27 atm)|
|Boiling point||−84 °C; −119 °F; 189 K (Sublimation point at 1 atm)|
|Solubility in water||slightly soluble|
|Std enthalpy of
|Autoignition temperature||300 °C; 572 °F; 573 K|
(what is: / ?)|
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Acetylene (systematic name: ethyne) is the chemical compound with the formula C2H2. It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in pure form and thus is usually handled as a solution. Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities.
As an alkyne, acetylene is unsaturated because its two carbon atoms are bonded together in a triple bond. The carbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180°. Since acetylene is a linear symmetrical molecule, it possesses the D∞h point group.