chlore

Traductions

• anglais

  Date : 1983

  Définition

  An element. State: gas; group: VIIA; atomic no.: 17; atomic wt.: 35,453; valence: 1,3,4,5,7; isotopes: 2 stable. Discovered in 1774 by Carl Wilhelm Scheele, a Swedish chemist (1742-1786), chlorine at room temperature is a heavy, yellowish gas but can easily be liquefied, b.p. -34.5 °C (-30 °F). A highly reactive chemical, it is a member of the halogen family; it is a strong electron acceptor (electronegative) and thus is a powerful oxidizing agent. In addition to its elemental form, chlorine exists in the valance states of -1, +1, +3, +4, +5 and +7, indicative of its great reactivity. It is made industrially by subjecting sodium chloride to electrolysis in solution (electrolytic cell) or in molten form.

  Notes :

  The isotopic composition of chlorine is unique, as one of its two isotopes comprises about 25 % of the element. Chlorine is unusually capable of forming ionic bonds and free radicals. It is toxic when inhaled as a gas and is a strong skin irritant as a liquid. A versatile element, chlorine is used at the rate of millions of tons per year in the manufacture of a broad range of chemicals, both organic and inorganic; among these are fluorocarbon, insecticides, plastics, and hydrochloric acid. It is an intermediate in making ethylene oxide and tetraethyllead and a constituent of many chlorinated hydrocarbons used as solvents (carbon tetrachloride). It is a basic ingredient of bleaches and an important bactericide, for which purpose it is used in water purification.
  
  The name ((is)) derived from the greek word for green. Although discovered by Scheele, Humphry Davy gave chlorine its name and delineated it as an element. In erroneous typography it may appear as C1 or CL.

  Terme :

  1. chlorine