Question

what is meaning of halogen

Answer 1

Any of the elements fluorine, chlorine, bromine, iodine, and astatine, occupying group VIIA (17) of the periodic table. They are reactive non-metallic elements which form strongly acidic compounds with hydrogen from which simple salts can be made.

Answer 2

Denoting lamps and radiant heat sources using a filament surrounded by the vapour of iodine or another halogen.

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