ethylene (redirected from Ethylene (plant hormone))

ethylene (ĕth`əlēn') or ethene (ĕth`ēn), H₂C=CH₂, a gaseous unsaturated hydrocarbon. It is the simplest alkene. Ethylene is colorless, has a faint odor, and has a slightly sweet taste; it melts at −169.4°C; and boils at −103.8°C;. Because of the presence of the double bond in its molecule, ethylene is very reactive. It burns in air with a luminous flame and forms explosive mixtures with pure oxygen. It combines directly with the halogens, e.g., with chlorine to form 1,2-dichloroethane. With hydrogen it forms ethane. Ethylene may be prepared by the dehydration of ethanol with sulfuric acid at about 180°C;. It is prepared commercially from natural gas and petroleum, e.g., by cracking and fractional distillation. Ethylene has many uses. It is important in the synthesis of many chemicals. It is used in making polyethylene and saran, in the manufacture of ethanol and ethylene oxide, and as an anesthetic. Ethylene was called olefiant gas by early chemists.

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ethylene

Simplest olefin (CH₂CH₂), a colourless, flammable gas with a sweetish taste and odour. The petrochemical having the highest volume, it occurs in petroleum and natural gas but is usually produced by heating higher hydrocarbons (usually ethane and ethane-propane mixtures). Ethylene is polymerized to polyethylene either at high pressures and temperatures or by catalysis. It reacts with numerous other chemicals to produce ethanol, solvents, gasoline additives, antifreeze, detergents, and various plastics. In plants, ethylene is a hormone that inhibits growth and promotes leaf fall and fruit ripening.