dibromine

Dibromine, also known as bromine or elemental bromine, is a chemical element with the symbol Br and atomic number 35. It is a member of the halogen group, along with fluorine, chlorine, iodine, and astatine. At room temperature and pressure, dibromine is a diatomic molecule, Br₂, consisting of two bromine atoms joined by a covalent bond. It is a reddish-brown, volatile liquid that readily evaporates to form a reddish-brown gas.

Dibromine is highly reactive and a strong oxidizing agent. It reacts with many elements and compounds, often vigorously. It is toxic and corrosive, causing severe burns upon contact with skin and irritation to the respiratory system. Inhalation of dibromine vapor can be harmful. Due to its reactivity and hazardous nature, dibromine is typically handled with extreme caution in laboratory and industrial settings, often requiring specialized equipment and ventilation.

The primary industrial source of dibromine is bromide salts found in seawater and underground brines. These bromide salts are oxidized to elemental bromine using chlorine gas. Dibromine has various applications, including in the production of flame retardants, agricultural chemicals, pharmaceuticals, and dyes. It is also used as a laboratory reagent in organic synthesis. Historically, dibromine was used in photographic processes and as a fumigant. Its use has declined in some areas due to environmental and health concerns, leading to the development of safer alternatives.