A common use of ethyne, also called acetylene, is as a fuel in welding. An acetylene flame can reach temperatures of close to 6,000 degrees Fahrenheit. Acetylene is also used for making carbon volatile to make it more efficient in carbon dating.
Ethyne was used for lighting, especially for the portable lamps used by miners and in the headlights of early automobiles. Ethyne is also used to harden steel that is too big to be hardened in a furnace. When ethyne is turned into ethylene, it can be used to make polyethylene plastic.
Ethyne in its pure form is an odorless, colorless gas. Its molecular formula is also simple. It is a chain made of two hydrogen atoms and two carbon atoms. Because the carbon atoms have a triple bond, they store a great deal of potential energy. This is expressed as heat in the acetylene torch.
Acetylene is obtained by the combustion of methane, a gas made of a molecule of a single carbon atom bonded to four hydrogen atoms. It's also a byproduct of the breakdown of complex hydrocarbons into simpler hydrocarbons. Acetylene also used to be a source of organic compounds through the hydrolysis of calcium carbide, a process that necessitated great amounts of heat.