Chlorine: Chemical Element Properties

Chlorine is a chemical element with the symbol Cl and it’s atomic number is 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. It was Discovered in 1774 by Carl Wilhelm Scheele, who mistakenly thought it contained oxygen. Chlorine was given its name in 1810 by Humphry Davy, who insisted that it was in fact an element. It is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent among the elements, it has the highest electron affinity and the third highest electronegativity on the Pauling scale, behind only oxygen and fluorine.


Uses of Chlorine

  • It is also used widely in the manufacture paper product production, antiseptic, dyestuffs, food, insecticides, paints, petroleum products, plastics, medicines, textiles, solvents, and many other consumer products.
  • It is used to kill bacteria and other microbes from drinking water supplies.
  • Chlorine is involved in bleaching wood pulp for paper making, bleach is also used industrially to remove ink from recycle paper.
  • Chlorine often imparts many desired properties in an organic compound when it is substituted for hydrogen (synthetic rubber), so it is widely used in organic chemistry, in the production of chlorates, chloroform, carbon tetrachloride, and in the bromine extraction.

Physical And Chemical Properties of Chlorine

  • Chlorine is a greenish yellow gas at room temperature and atmospheric pressure. It is two and a half times heavier than air. It becomes a liquid at −34 °C (−29 °F).
  • It has a choking smell, and inhalation causes suffocation, constriction of the chest, tightness in the throat, and after severe exposure edema (filling with fluid) of the lungs. As little as one part per thousand in air causes death within a few minutes, but less than one part per million may be tolerated.
  • Chlorine has a high electronegativity and a high electron affinity, the latter being even slightly higher than that of fluorine. The affinity of chlorine for hydrogen is so great that the reaction proceeds with explosive violence in light.
  • Chlorine molecules are composed of two atoms (Cl2). Chlorine combines with almost all the elements, except for the lighter noble gases, to give chlorides; those of most metals are ionic crystals, whereas those of the semimetals and nonmetals are predominantly molecular.