Atomic Number: | 17 | Atomic Symbol: | Cl |
Atomic Weight: | 35.453 | Electron Configuration: | 2-8-7 |
Shells: | 2,8,7 | Filling Orbital: | 3p5 |
Melting Point: | 97.8oC | Boiling Point: | 882.9oC |
Uses: | salt, water purification, bleaches, CFCs etc. |
History
(Gr. chloros, greenish yellow) Discovered in 1774 by Carl
Wilhelm Scheele, who thought it contained oxygen. Chlorine was named in 1810 by
Davy, who insisted it was an element.
Sources
In nature it is found in the combined state only, chiefly with
sodium as common salt (NaCl), carnallite, and sylvite.
Properties
It is a member of the halogen (salt-forming) group of
elements and is obtained from chlorides by the action of oxidizing agents and
more often by electrolysis; it is a greenish-yellow gas, combining directly with
nearly all elements. At 10C one volume of water disolves 3.10 volumes of
chlorine, at 30C only 1.77 volumes.
Uses
Chlorine is widely used in making many everyday products. It is
used for producing safe drinking water the world over. Even the smallest water
supplies are now usually chlorinated.
It is also extensively used in the production of paper products, dyestuffs,
textiles, pretoleum products, medicines, antiseptics, insecticides, food,
solvents, paints, plastics, and many other consumer products.
Most of the chlorine produced is used in the manufacture of chlorinated
compounds for sanitation, pulp bleaching, disinfectants, and textile processing.
Further use is in the manufacture of chlorates, chloroform, carbon
tetrachloride, and in the extraction of bromine.
Organic chemistry demands much from chlorine, both as an oxidizing agent and
in substitution, since it often brings many desired properties in an organic
compound when substituted for hydrogen, as in one form of synthetic rubber.
Handling
Chlorine is a respiratory irritant. The gas irritates the
mucous membranes and the liquid burns the skin. As little as 3.5 ppm can be
detected as an odor, and 1000 ppm is likely to be fatal after a few deep
breaths. In fact, chlorine was used as a war gas in 1915.
Exposure to chlorine should not exceed 0.5 ppm (8-hour time-weighted average
- 40 hour week.)