Chlorine

From Citizendium, the Citizens' Compendium
Jump to: navigation, search
This article is a stub and thus not approved.
Main Article
Talk
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
Properties [?]
 
This editable Main Article is under development and not meant to be cited; by editing it you can help to improve it towards a future approved, citable version. These unapproved articles are subject to a disclaimer.
Chlorine
35.453(2)



  Cl
17
1s22s22p63s23p5
[ ? ] Halogen:
Properties:
Pale yellow-green, toxic gas with strong odor.
Uses:
Water purification, bleaching, disinfection, dyestuffs, medicines.
Hazard:
Toxic, explosive in mixtures with flammable gases and vapors.


Chlorine is a chemical element, having the chemical symbol Cl. Its atomic number (the number of protons) is 17. It has a standard atomic weight of 35.453 g•mol −1, and is typically found as a solid in its elemental form.

Chlorine is considered a member of the "Halogen" class of element. At a pressure of 101.325 kPa, it has a boiling point −34.04 °C, and a melting point of −101.5 °C.

Chemical warfare

Chlorine was the first agent used as a large-scale chemical weapon, by German forces at the Second Battle of Ypres in 1915; see World War I, poison gas. It was released from cylinders carried by trains, but was replaced by agents that were sufficiently toxic, for weight, to be used in artillery shells (e.g., phosgene).

Concern remains that chlorine, widely used in water purification and as an industrial chemical precursor, could be the source of a chemical terrorism incident. In industrialized countries, greater tracking and security is being applied to the large amounts shipped by rail.