halogens definition chemistry
Halogen Definition: A element located in Group VIIA of the periodic table. Halogens are reactive nonmetals having seven valence electrons. Examples: fluorine, chlorine, bromine, iodine. Return to the Chemistry Glossary Index. By Anne Marie Helmenstine, Ph.D.alogen Definition: A element located in Group VIIA of the periodic table. Halogens are reactive nonmetals having seven valence electrons. Examples: fluorine, chlorine, bromine, iodine. Return to the Chemistry Glossary Index. By Anne Marie Helmenstine, Ph.D.