Acetylene

Acetylene is a chemical compound with the formula C₂H₂ and has the structure HC≡CH.

It is a colorless and odorless gas.

Uses

Acetylene is highly flammable and when mixed with oxygen it gives the hottest flame of any common fuel gas, reaching over 3000 °C (5432 °F), making it useful for manipulating metal.

Steel Welding/Cutting

Before arc welders were invented, acetylene torches were a common method of welding steel together. They can also be used to cut steel, however their use is limited as the heat created can ruin any heat treatment that has been done on a metal.

Brazing

Brazing is the joining of two pieces of metal using a Solder of another metal. For example, Brass is sometimes used to braze the steel frames of bikes.

Acetylene can provide localized heating in order to do this method of joining metal.

Production

The historical method of production is the chemical reactions between calcium carbide and water.

CaC₂ + 2H₂O → Ca(OH)₂ + C₂H₂