chlorine

A highly irritating, greenish-yellow halogen element, existing as a diatomic gas, Cl₂, and capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to disinfect water, as a bleaching agent, and in the manufacture of many important compounds including chlorates, sodium hypochlorite, and chloroform. Atomic number 17; atomic weight 35.453; freezing point -100.5°C; boiling point -34.04°C; specific gravity 1.56 (-33.6°C); valence 1, 3, 5, 7. See Periodic Table.

(Elements & Compounds) a toxic pungent greenish-yellow gas of the halogen group; the 15th most abundant element in the earth's crust, occurring only in the combined state, mainly in common salt: used in the manufacture of many organic chemicals, in water purification, and as a disinfectant and bleaching agent. Symbol: Cl; atomic no: 17; atomic wt: 35.4527; valency: 1, 3, 5, or 7; density: 3.214 kg/m³; relative density: 1.56; melting pt: –101.03°C; boiling pt: –33.9°C

Symbol Cl A greenish-yellow, gaseous halogen element that can combine with most other elements and is found chiefly in combination with sodium as common salt. Chlorine is very poisonous, being highly irritating to the nose, throat, and lungs, and causing suffocation. It is used in purifying water, as a disinfectant and bleach, and in making many important compounds such as chloroform. Atomic number 17. See Periodic Table. See Note at chlorophyll.