Ethane (C2H6) is the second member of the alkane series of
hydrocarbons. Ethane occurs in natural
gas and is one of the products of petroleum cracking.
It is a colorless, odorless, flammable gas, which forms an explosive mixture
|A ball-and-stick model of the ethane molecule, made
up of two carbon atoms (blue spheres) and six hydrogen atoms (green
spheres). In terms of symmetry, it has a center of inversion (I) but
the two methyl (CH3) groups are not related by a mirror
plane between them. These groups can mutually rotate into alignment,
giving the molecule such a mirror plane but destroying the center
of inversion. (Molecular symmetry and its alteration with internal
motion dominates much of chemical theory.
Ethane may be prepared by reduction of ethene
or ethyne by hydrogen under pressure in
the presence of a nickel catalyst, or by
the electrolysis of a solution of potassium ethanoate.
Ethane is used in low-temperature refrigeration plant. It has been detected
as a trace component in the atmospheres of Jupiter, Saturn, Uranus, and
Neptune, and in the atmosphere of Saturn's largest moon Titan.
||-182.7°C (90.3 K)
||-88.6°C (184.5 K)