One of the elementary substances, commonly isolated as a greenish yellow gas, two and one half times as heavy as air, of an intensely disagreeable suffocating odor, and exceedingly poisonous. It is abundant in nature, the most important compound being common salt. It is powerful oxidizing, bleaching, and disinfecting agent. Symbol Cl. Atomic weight, 35.4.
- A highly irritating, greenish-yellow gaseous halogen, capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to purify water, as a disinfectant and bleaching agent, and in the manufacture of many important compounds including chloroform and carbon tetrachloride. Atomic number 17; atomic weight 35.453; freezing point -100.98°C; boiling point -34.6°C; specific gravity 1.56 (-33.6°C); valence 1, 3, 5, 7. See Table at element.