On the periodic table, bromine is the halogen that is liquid at room temperature.
Bromine has atomic number 35 and belongs to group 17. It is a dense, volatile liquid with a reddish-brown color and a strong odor. Like other halogens, bromine is reactive and usually occurs in nature as bromide compounds rather than as free elemental bromine.
Bromine’s position below chlorine and above iodine helps explain its intermediate properties. It is less reactive than chlorine but more reactive than iodine. Bromine compounds have been used in photography, flame retardants, medicines, and industrial chemistry, although particular uses have changed because of environmental and health concerns.
At ordinary room conditions, bromine is the only nonmetallic element that is liquid. Mercury is also liquid near room temperature, but it is a metal, not a halogen.