|Boiling Point: 332.4°K, 59.25°C,
Melting Point: 266.05°K, -7.1°C, 19.2°F
Electrons Energy Level: 2, 8, 18, 7
Isotopes: 25 + 2 Stable
Heat of Vaporization: 15.438 kJ/mol
Heat of Fusion: 5.286 kJ/mol
Density: 3.119g/cm3 @ 300°K
Specific Heat: 0.473 J/g°K
Atomic Radius: 1.12Å
Ionic Radius: 1.96Å
Electronegativity: 2.96 (Pauling); 2.74 (Allrod Rochow)
Vapor Pressure: 5800 Pa @ -7.1°C
|Bromine is a reddish-brown fuming liquid at room temperature with a very disagreeable
chlorine-like smell. In fact its name is derived from the Greek bromos or
"stench". The only nonmetallic element that is a liquid at normal room
temperatures, Bromine was produced by Carl Löwig, a young chemistry student, the summer
before starting his freshman year at Heidelberg. When he showed his professor,
Leopold Gmelin, the red, smelly liquid he had produced,
Gmelin realized that this was an unknown substance and encouraged Löwig to produce more
of it so they could study it in detail. Unfortunately, winter exams and the
holidays delayed Löwig's work long enough for another chemist, Antoine-Jérôme Balard,
to publish a paper in 1826 describing the new element he had isolated in pure form at the
salt marshes of Monpellier. It was not produced in quantity until 1860. The
French chemist and physicist Joseph-Louis Gay-Lussac suggested the name Bromine due to the
characteristic smell of the vapors.
Most Bromine is produced by displacement from ordinary sea water. Chlorine (which is more active) is generally used to dislodge the Bromine from various compounds in the water. Before leaded gasolines were removed from the market, Bromine was used in an additive to help prevent engine "knocking". Production now is chiefly devoted to dyes, disinfectants and photographic chemicals.
1s2 2s2p6 3s2p6d10 4s2p5
Bromine is the only liquid nonmetallic element at room temperature and one of five elements on the period table that are liquid at or close to room temperature. The pure chemical element has the physical form of a diatomic molecule, Br2. It is a heavy, mobile, reddish-brown liquid, that evaporates easily at standard temperature and pressues (273oK & 1 Atm.) in a red vapor (its color resembles Nitrogen Dioxide, NO2) that has a strong disagreeable odor resembling that of Chlorine. A halogen, Bromine resembles Chlorine chemically but is less active. It is more active than Iodine, however. Bromine is slightly soluble in water, and highly soluble in Carbon Disulfide, CS2, aliphatic alchohols (such as Methanol (CH3OH), and Acetic Acid, CH3COOH. It bonds easily with many elements and has a strong bleaching action.
Bromine is highly reactive and is a powerful oxidizing agent in the presence of water. It reacts vigorously with Amines, Alkenes and Phenols as well as aliphatic and Aromatic Hydrocarbons, Ketones and Acids (these are brominated by either addition or substitution reactions). With many of the metals and elements, anhydrous Bromine is less reactive than hydrated Bromine; however, dry Bromine reacts vigorously with Aluminum, Titanium, Mercury, as well as alkaline earth metals and alkaline metals.
Elemental Bromine is used to manufacture a wide variety of Bromine compounds used in industry and agriculture. Traditionally the largest use of bromine was in the production of 1,2-Dibromoethane which in turn was used as a gasoline anti-knock agent for leaded gasolines before they were largely phased out due to environmental considerations.
Bromine is also used in the manufacture of fumigants, brominated flame-retardants, water purification compounds, dyes, medicines, sanitizers, imorganic bromides for photography, etc. It is also used to form intermediates in organic synthesis, where it is preferred to Iodine due to its much lower cost.
Bromine is used to make brominated vegetable oil, which is used as an emulsifier in many citrus-flavored soft drinks.
Aqueous Bromine is orange and can be used in tests for Alkenes and Phenols.
Bromine occurs in nature as bromide salts in very diffuse amounts in crustal rock. Due to leaching, bromide salts have accumulated in sea water (85 ppm), and may be economically recovered from brine wells and the Dead Sea (up to 5000 ppm). Due to its contribution to Ozone depletion in Earth's atmosphere, Bromine has been evaluated to have an Ozone depletion potential of 60 when compared to Chlorine.
Approximately 500 million kilograms ($350 million USD) of Bromine are produced per year (2001) worldwide with the United States and Israel being the primary producers. The largest Bromine reserve in the United States is located in Columbia and Union County, Arkansas.
|Elemental Bromine is a strong irritant and, in concentrated form, will produce painful blisters on exposed skin and especially mucous membranes. Even low concentrations of Bromine vapor (from 10 ppm) can affect breathing, and inhalation of significant amounts of Bromine can seriously damage the respiratory system.|
It is the only non-metal that is a liquid at normal room conditions. Bromine on the skin causes painful burns that heal very slowly. It is an element to be treated with the utmost respect in the laboratory. Accordingly, one should always wear safety gogglesand ensure adequate ventilation when handling Bromine.
In laboratory settings, bromine should always be kept separate from Acetone, CH3COCH3, as the two chemicals will react and create Bromoacetone, a potentially hazardous lachrymatory agent.
Elemental Bromine is a hazardous material. It causes severe burns when it comes in contact with the skin and its vapor irritates the eyes, nose and throat. Most of the Bromine produced in the United States was used in the manufacture of Ethylene Dibromide(C2H4Br2), a chemical added to leaded gasolines that prevented the accumulation of lead compounds within the engine. With the discontinuation of leaded gasolines in favor of unleaded gasolines, the demand for Bromine has been greatly reduced. Silver Bromide (AgBr), a chemical used in photography, now accounts for the largest use of Bromine. Other Bromine compounds are used in fumigants, in flameproofing agents and in some compounds used to purify water. Tyrian purple, an expensive purple dye known to ancient civilizations, was produced from an organic Bromine compound secreted from a sea mussel known as the murex.
|Aluminum Bromide (AlBr3)||Ammonium Bromide (NH4Br)|
|Bromine Monofluoride (BrF)||Bromine Pentafluoride (BrF5)|
|Bromine trifluoride (BrF3)||Tetrabromomethane (CBr4)|
|Hydrobromic Acid (HBr)||Iron (III) Bromide (FeBr3)|
|Lithium Bromide (LiBr)||Phosphorus Pentabromide (PBr5)|
|Phosphorus Tribromide (PBr3)||Potassium Bromide (KBr)|
|Potassium Bromate (KBrO3)||Silver Bromide (AgBr)|
|Sodium Bromide (NaBr)||Sodium Bromate (NaBrO3)|
(Gr. bromos, stench) Discovered by Balard in 1826, but not prepared in quantity until 1860. A member of the halogen group of elements, it is obtained from natural brines from wells in Michigan and Arkansas. Little bromine is extracted today from seawater, which contains only about 85 ppm. Bromine is the only liquid nonmetallic element. It is a heavy, mobile, reddish-brown liquid, volatilizing readily at room temperature to a red vapor with a strong disagreeable odor, resembling chlorine, and having a very irritating effect on the eyes and throat; it is readily soluble in water or carbon disulfide, forming a red solution, is less active than chlorine but more so than iodine; it unites readily with many elements and has a bleaching action; when spilled on the skin it produces painful sores. It presents a serious health hazard, and maximum safety precautions should be taken when handling it. Much of the bromine output in the U.S. was used in the production of ethylene dibromide, a lead scavenger used in making gasoline antiknock compounds. Lead in gasoline, however, has been drastically reduced, due to environmental considerations. This will greatly affect future production of bromine. Bromine is also used in making fumigants, flameproofing agents, water purification compounds, dyes, medicinals, sanitizers, inorganic bromides for photography, etc. Organic bromides are also important.
Source: CRC Handbook of Chemistry and Physics, 1913-1995. David R. Lide, Editor in Chief. Author: C.R. Hammond
Atomic Radius (Å): 1.12Å
Electrochemical Equivalents: 2.9812 g/amp-hr
Atomic Mass Average: 79.904