A reddish-brown volatile element of the halogen group found in compounds occurring in ocean water. The pure form is a nonmetallic liquid that gives off a highly irritating vapor. It is used to make dyes, sedatives, and photographic film. Atomic weight 79.904; atomic number 35; melting point 7.2°C; boiling point 58.78°C; specific gravity 3.12; valence 1, 3, 5, 7. See
Periodic Table.