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Chlorine • Halogen

Primary XPS region: Cl2p
Overlapping regions: Se LMM, As3s
Binding energies of common chemical states:

Chemical state Binding energy Clp3/2 / eV
Organic Cl 200
Metal chloride ~198.5–199

Experimental Information

Interpretation of XPS Spectra

General comments

hexAbout This Element

Symbol: Cl
Date of Discovery: 1774
Name Origin: Greek khlôros
Appearance: green
Discoverer: Carl Wilhelm Scheele
Obtained From: salt

Melting Point: -100.98 K
Boiling Point: -34.6 K
Density[kg/m3]: 3.214
Molar Volume: 17.39 × 10-6 m3/mol
Protons/Electrons: 17
Neutrons: 18
Shell Structure: 2,8,7
Electron Configuration: [Ne]3s23p5
Oxidation State: ±1,3,5,7
Crystal Structure: Orthorhombic

Chlorine is a greenish yellow gas that combines with nearly all elements. In nature, chlorine is found as the chloride ion that is deposited in the earth or dissolved in the oceans. High concen- trations of chloride are found in the Dead Sea, and about 1.9% of the mass of the world’s sea water is chloride. Chlorine gas was used against humans in World War I as a killing agent. Chlorine is an ingredient in many everyday items and is an important chemical in water purification, disinfectants, and bleach.


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