Atomic number:17

Group numbers:17

Period:3

Electronic configuration:[Ne] 3s² 3p⁵

Formal oxidation number:-1 +1 +5 +7

Electronegativities:3.16

Atomic radius / pm:99.4

Relative atomic mass:35.453 ± 0.002

 

Chlorine was discovered by Carl William Scheele (SE) in 1774. The origin of the name comes from the Greek word chloros meaning pale green. It is a greenish-yellow, disagreeable gas with irritating odour. The gas is toxic and severe irritant by contact or inhalation. It's Never found in free form in nature. Commercial quantities of chlorine are produced by electrolysis of aqueous sodium chloride (NaCl) from seawater or brine from salt mines. Sulfur is used in water purification, bleaches, acids and many, many other compounds such as chlorofluorocarbons (CFC).

Density / g dm^-3:2030 (113 K)

 1507 (239 K)

 3.214 (273 K)

Molar volume / cm³mol^-1:17.46 (113 K)

 23.53 (239 K)

 22061.61 (273 K)

Electrical resistivity / μΩcm:- (20 °C)

Thermal conductivity / W m^-1K^-1:0.0089

Melting point / °C:-101.5

Boiling point / °C:-34.04

Heat of fusion / kJ mol^-1:6.41

Heat of vaporization / kJ mol^-1:20.4033

Heat of atomization / kJ mol^-1:120

1st ionization energy / kJ mol^-1:1251.20

2nd ionization energy / kJ mol^-1:2297.72

3rd ionization energy / kJ mol^-1:3821.81

in the atmosphere / ppm:-

in the Earth's crust / ppm:130

in the oceans / ppm:19000