Bromine water, because of the easy oxidation of bromide to the equivalent of Br, a potent electrophile. The enzyme bromoperoxidase catalyzes this reaction. The oceans are estimated to release 1–2 million tons of bromoform and 56,000 tons of bromomethane annually. An old qualitative test for the presence of the alkene functional group is that alkenes turn brown aqueous bromine solutions colourless, forming a bromohydrin with some of the dibromoalkane also produced. The reaction passes through a short-lived strongly electrophilic bromonium intermediate. This is an example of a halogen addition reaction. Bromine is significantly less abundant in the crust than fluorine or
Bromine production in the United States rail access, and difficult highway access, and was shut down in 1945. Dow found a better permanent location at Freeport, Texas, where a seawater extraction plant started in 1940, and a second in 1943. The Freeport plants recovered magnesium, sodium compounds, and chlorine, in addition to the bromine. The Freeport chemical operations are still active, but they stopped extracting bromine in 1969. Brine mining Bromine production in the United States Bromine production in the United States of 225,000 tonnes in 2013 made that country the second-largest producer of bromine, after Israel. The US supplied 29 percent of world production. Since