Methane << METH ayn >> is an important industrial compound that makes up a large part of natural gas. On Earth, it commonly forms when plants decay in places where there is very little oxygen. Methane is often called marsh gas because it is found around stagnant water and swamps. It is also the chief substance in firedamp, a gas that causes serious explosions in mines.
The chemical industry uses methane as a starting material for many other chemicals. Methane reacts at high temperatures with a limited amount of air to form acetylene and with ammonia to produce hydrogen cyanide. It also undergoes partial combustion (incomplete burning), producing hydrogen and carbon monoxide gases. This mixture serves as a source for commercial hydrogen and for carbon monoxide used in making methyl alcohol (methanol).
Methane is a colorless, odorless gas. It is nontoxic but highly flammable. It is soluble in alcohol but only slightly soluble in water. It is the simplest of the hydrocarbons, a class of compounds that contain only hydrogen and carbon. Mixtures of methane with air, oxygen, or chlorine are explosive. Methane is a significant part of the atmospheres of Jupiter, Saturn, Neptune, and Uranus.
See also Acetylene; Damp; Gas (The composition of natural gas); Hydrocarbon; Methanol.
