Bromine

Antoine Jérôme Balard 1870s

Bromid stříbrný

N-Bromosuccinimide

Alkene-bromine-addition-2D-skeletal

STS028-96-65

Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly colored gas. Its properties are thus intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name comes from the Ancient Greek βρῶμος ("stench"), referencing its sharp and pungent smell.

Properties

Bromine is less reactive than chlorine and more reactive than iodine. It is soluble in organic solvents like carbon disulfide, chloroform, and carbon tetrachloride, as well as in water. Its compounds are used in agriculture, photography, and as fire retardants. Bromine's high reactivity makes it useful in many chemical syntheses, where it is used to make a variety of brominated compounds, including some types of plastics and flame retardants.

Occurrence

Bromine is significantly less abundant in the Earth's crust than chlorine. It is mainly extracted from brine pools, especially in the United States and China. The largest use of bromine is in the production of brominated flame retardants. It is also important in the manufacture of pesticides, pharmaceuticals, and various bromide compounds.

Health and Safety

Bromine is a hazardous material, as it is both corrosive and toxic. Exposure to bromine liquid or gas can cause irritation to the skin, eyes, and mucous membranes. Ingestion or inhalation of bromine can lead to severe poisoning. Safety measures include using bromine in well-ventilated areas, wearing protective clothing, and having proper storage for bromine-containing compounds.

Applications

Bromine is used in a number of areas including:

• Flame retardants: Brominated flame retardants are used in a wide range of electronics, textiles, and furniture to prevent fires.
• Pharmaceuticals: Some bromine compounds are used in medication, including sedatives and antiepileptics.
• Agriculture: Bromine compounds are used as pesticides.
• Photography: Bromine is used in the manufacture of photographic film and emulsions.
• Water treatment: Bromine compounds are used in swimming pools and spa sanitizers to kill bacteria and algae.

Environmental Impact

Brominated flame retardants have raised environmental concerns due to their persistence and potential to bioaccumulate. Studies have shown that these compounds can disrupt endocrine systems in wildlife and humans, leading to regulatory actions and the search for safer alternatives.

See Also

• Halogen
• Chlorine
• Iodine
• Flame retardant
• Environmental impact of flame retardants