Bromine is a chemical element; it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig and Antoine Jérôme Balard, its name was derived from Ancient Greek βρῶμος (bromos) 'stench', referring to its sharp and pungent smell.
1,2-Dibromoethane, also known as ethylene dibromide (EDB), is an organobromine compound with the chemical formula C
2H
4Br
2. Although trace amounts occur naturally in the ocean, where it is probably formed by algae and kelp, substantial amounts are produced industrially. It is a dense colorless liquid with a faint, sweet odor, detectable at 10 ppm. It is a widely used and sometimes-controversial fumigant. The combustion of 1,2-dibromoethane produces hydrogen bromide gas that is significantly corrosive.
In organic chemistry, an aryl halide is an aromatic compound in which one or more hydrogen atoms, directly bonded to an aromatic ring are replaced by a halide. Haloarenes are different from haloalkanes because they exhibit many differences in methods of preparation and properties. The most important members are the aryl chlorides, but the class of compounds is so broad that there are many derivatives and applications.
Polybrominated diphenyl ethers or PBDEs, are a class of organobromine compounds that are used as flame retardants. Like other brominated flame retardants, PBDEs have been used in a wide array of products, including building materials, electronics, furnishings, motor vehicles, airplanes, plastics, polyurethane foams, and textiles. They are structurally akin to polychlorinated diphenyl ethers (PCDEs), polychlorinated biphenyls (PCBs) and other polyhalogenated compounds, consisting of two halogenated aromatic rings. PBDEs are classified according to the average number of bromine atoms in the molecule. The life-saving benefits of fire retardants led to their popularization. Standards for mass transit vehicles continues to increase as of 2021.
Flame retardants are a diverse group of chemicals that are added to manufactured materials, such as plastics and textiles, and surface finishes and coatings. Flame retardants are activated by the presence of an ignition source and prevent or slow the further development of flames by a variety of different physical and chemical mechanisms. They may be added as a copolymer during the polymerisation process, or later added to the polymer at a moulding or extrusion process or applied as a topical finish. Mineral flame retardants are typically additive, while organohalogen and organophosphorus compounds can be either reactive or additive.
Bromoform is an organic compound with the chemical formula CHBr3. It is a colorless liquid at room temperature, with a high refractive index and a very high density. Its sweet odor is similar to that of chloroform. It is one of the four haloforms, the others being fluoroform, chloroform, and iodoform. It is a brominated organic solvent. Currently its main use is as a laboratory reagent. It is very slightly soluble in water and is miscible with alcohol, benzene, chloroform, ether, petroleum ether, acetone and oils.
A bromide ion is the negatively charged form (Br−) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. Although uncommon, chronic toxicity from bromide can result in bromism, a syndrome with multiple neurological symptoms. Bromide toxicity can also cause a type of skin eruption, see potassium bromide. The bromide ion has an ionic radius of 196 pm.
Brominated flame retardants (BFRs) are organobromine compounds that have an inhibitory effect on combustion chemistry and tend to reduce the flammability of products containing them. The brominated variety of commercialized chemical flame retardants comprise approximately 19.7% of the market. They are effective in plastics and textile applications like electronics, clothes, and furniture. 390,000 tons of brominated flame retardants were sold in 2011. This represents 19.7% of the flame retardants market.
Arsenic tribromide is an inorganic compound with the formula As Br3, it is a bromide of arsenic. Arsenic is a chemical element that has the symbol As and atomic number 33. This pyramidal molecule is the only known binary arsenic bromide. AsBr3 is noteworthy for its very high refractive index of approximately 2.3. It also has a very high diamagnetic susceptibility. The compound exists as colourless deliquescent crystals that fume in moist air.
Bromine compounds are compounds containing the element bromine (Br). These compounds usually form the -1, +1, +3 and +5 oxidation states. Bromine is intermediate in reactivity between chlorine and iodine, and is one of the most reactive elements. Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine. This can be seen from the standard electrode potentials of the X2/X− couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V). Bromination often leads to higher oxidation states than iodination but lower or equal oxidation states to chlorination. Bromine tends to react with compounds including M–M, M–H, or M–C bonds to form M–Br bonds.
Magnesium bromide are inorganic compounds with the chemical formula MgBr2(H2O)x, where x can range from 0 to 9. They are all white deliquescent solids. Some magnesium bromides have been found naturally as rare minerals such as: bischofite and carnallite.
Decabromodiphenyl ether is a brominated flame retardant which belongs to the group of polybrominated diphenyl ethers (PBDEs). It was commercialised in the 1970s and was initially thought to be safe, but is now recognised as a hazardous and persistent pollutant. It was added to Annex A of the Stockholm Convention on Persistent Organic Pollutants in 2017, which means that treaty members must take measures to eliminate its production and use. The plastics industry started switching to decabromodiphenyl ethane as an alternative in the 1990s, but this is now also coming under regulatory pressure due to concerns over human health.
Pentabromodiphenyl ether is a brominated flame retardant which belongs to the group of polybrominated diphenyl ethers (PBDEs). Because of their toxicity and persistence, their industrial production is to be eliminated under the Stockholm Convention, a treaty to control and phase out major persistent organic pollutants (POP).
Lead(II) bromide is the inorganic compound with the formula PbBr2. It is a white powder. It is produced in the burning of typical leaded gasolines.
Cobalt(II) bromide (CoBr2) is an inorganic compound. In its anhydrous form, it is a green solid that is soluble in water, used primarily as a catalyst in some processes.
Organobromine chemistry is the study of the synthesis and properties of organobromine compounds, also called organobromides, which are organic compounds that contain carbon bonded to bromine. The most pervasive is the naturally produced bromomethane.
Chromium(III) bromide is an inorganic compound with the chemical formula CrBr3. It is a dark colored solid that appears green in transmitted light but red with reflected light. It is used as a precursor to catalysts for the oligomerization of ethylene.
Lutetium(III) bromide is a crystalline compound made of one lutetium atom and three bromine atoms. It takes the form of a white powder at room temperature. It is hygroscopic. It is odorless.
A bromophenol is an organic compound consisting of hydroxyl groups and bromine atoms bonded to a benzene ring. They may be viewed as hydroxyl derivatives of bromobenzene, or as brominated derivatives of phenol. There are five basic types of bromophenols and 19 different bromophenols in total when positional isomerism is taken into account. Bromophenols are produced by electrophilic halogenation of phenol with bromine.
Bis(2-ethylhexyl)tetrabromophthalate (or TBPH), is a brominated phthalate derivative with the formula C24H34Br4O4 commonly used as a brominated flame retardant (BFR).
