General Description
A reddish-brown aqueous solution. The solubility of bromine in water equals 0.33 mg/ mL.
Reactivity Profile
BROMINE SOLUTION is an oxidizing agent. Bromine disproportionates rapidly in basic water to give bromide ion and bromate ion. The latter is also an oxidizing agent. Dissolution lowers reactivity compared to pure bromine. Reacts with reducing reagents. Reacts with hydrogen, diethylzinc, dimethylformamide, ammonia, trimethylamine, nitromethane, metal azides (silver or sodium azide). Can react with Mg, Sr, B, Al, Hg, Ti, Sn, Sb in powder or sheet form, to form bromides. Can react with methanol, ethanol, aldehydes, ketones, carboxylic acids, diethyl ether, carbonyl compounds, tetrahydrofuran, acrylonitrile, ozone, phosphorus, natural rubber. Reactions with red phosphorus, metal azides, nitromethane, silane and its homologues may be vigorous.[Bretherick, 5th ed., 1995, p. 109].
Air & Water Reactions
Slightly soluble in water.
Hazard
Toxic by ingestion and inhalation, severe
skin irritant. Strong oxidizing agent, may ignite
combustible materials on contact. Upper and lower
respiratory tract irritant, and lung damage.
Health Hazard
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
Potential Exposure
Bromine is primarily used in the manufacture
of gasoline antiknock compounds (1,2-dibromoethane).
Other uses are for gold extraction; in brominating
hydrocarbons; in bleaching fibers and silk; in the manufacture
of military gas, dyestuffs; and as an oxidizing agent. It is used
in the manufacture of many pharmaceuticals and pesticides.
Fire Hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
First aid
Move victim to fresh air. Call 911 or emergency
medical service. Give artificial respiration if victim is not
breathing. Do not use mouth-to-mouth method if victim
ingested or inhaled the substance; give artificial respiration
with the aid of a pocket mask equipped with a one-way valve
or other proper respiratory medical device. Administer oxygen
if breathing is difficult. Remove and isolate contaminated
clothing and shoes. In case of contact with substance,
immediately flush skin or eyes with running water for at
least 20 minutes. For minor skin contact, avoid spreading
material on unaffected skin. Keep victim warm and quiet.
Effects of exposure (inhalation, ingestion or skin contact) to
substance may be delayed. Ensure that medical personnel
are aware of the material(s) involved and take precautions to
protect themselves. Medical observation is recommended
for 24 to 48 hours after breathing overexposure, as pulmonary
edema may be delayed. As first aid for pulmonary
edema, a doctor or authorized paramedic may consider
administering a drug or other inhalation therapy.
Shipping
Bromine UN1744 Hazard class: 8; Labels: 8—
Corrosive material; 6.1—Poison Inhalation Hazard,
Inhalation Hazard Zone A. Bromine solutions, Hazard
class: 8; Labels: 8—Corrosives materials; 6.1—Poison
Inhalation Hazard, Inhalation Hazard Zone A; Bromine
solutions, Hazard class: 8 Labels: 8—Corrosive material;
6.1—Poison Inhalation Hazard, Inhalation Hazard Zone B.
Incompatibilities
A powerful oxidizer. May cause fire and
explosions in contact with organic or other readily oxidizable
materials. Contact with aqueous ammonia, acetaldehyde,
acetylene, acrylonitrile, or with metals, may cause violent
reactions. Anhydrous Br2 reacts with aluminum, titanium,
mercury, potassium; wet Br2 with other metals. Also incompatible
with alcohols, antimony, alkali hydroxides, arsenites,
boron, calcium nitrite, cesium monoxide, carbonyls,
dimethyl formamide, ethyl phosphine, fluorine, ferrous and
mercurous salts; germanium, hypophosphites, iron carbide,
isobutyronphenone, magnesium phosphide, methanol, nickel
carbonyl, olefins, ozone, sodium and many other substances.
Attacks some coatings, and some forms of plastic and rubber.
Corrodes iron, steel, stainless steel; and copper.
Chemical Properties
Bromine is a fuming red to dark reddishbrown,
nonflammable, volatile liquid with a suffocating
odor. Soluble in water and alcohol.
Chemical Properties
Butane, CH3(CH2)2CH3, also known as n-butane and methyl-ethyl methane,is a colorless gas that occurs in natural gas and is obtained by cracking petroleum. It is used as a refrigerant and as a fuel.
Waste Disposal
Large volumes of concentrated
solutions of reducing agents (bisulfites or ferrous
salts) may be added. The mixture is neutralized with
soda ash or dilute HCl and flushed to the sewer with large
volumes of water.
Physical properties
Bromine is a thick, dark-red liquid with a high density. It is the only nonmetallic elementthat is a liquid at normal room temperatures. (The other element that is liquid at room temperaturesis the metal mercury.) Bromine’s density is 3.12g/cm3, which is three times the density ofwater. Its vapor is much denser than air, and when it is poured into a beaker, the fumes hug thebottom of the container. Bromine’s melting point is –72°C, and its boiling point is 58.8°C.
Isotopes
There are a total of 40 isotopes of bromine. Of these, only two are stable: Br-79constitutes 50.69% of the stable bromine found on Earth, and Br-81 makes up 49.31%of the naturally occurring abundance. All the other isotopes of bromine are radioactivewith half-lives ranging from 1.2 nanoseconds to 16.2 hours.
Origin of Name
Named for the Greek word bromos, which means “stench.”
Occurrence
Bromine is the 62nd most abundant element found on Earth. Although it is not founduncombined in nature, it is widely distributed over the Earth in low concentrations. It isfound in seawater at a concentration of 65 ppm. This concentration is too low for the bromineto be extracted directly, so the salt water must be concentrated, along with chlorine and othersalts, by solar evaporation, distillation, or both.
Most of the commercial bromine that is recovered comes from underground salt minesand deep brine wells. A major source is the deep brine wells found in the state of Arkansas and Great Salt Lake of Utah in the United States. This brine contains about one-half percentbromine. Chlorine gas is added to hot brine that oxidizes the bromine ions in solution, whichis then collected as elemental bromine. It is also commercially produced, along with potash,from evaporation of the high-salt-content water of the Dead Sea, which is 1290 feet below sealevel and is located on the borders of the Middle Eastern countries of Israel and Jordan.
Characteristics
Bromine is a very reactive nonmetallic element, located between chlorine and iodine in theperiodic table. Bromine gas fumes are very irritating and toxic and will cause severe burns ifspilled on the skin.
Bromine is soluble in most organic solvents and only slightly soluble in H2O. Liquid brominewill attack most metals, even platinum.
Uses
A major use is as a gasoline additive called ethylene dibromide, an antiknock agent thatremoves lead additives from automobile engines after the combustion of leaded gasoline, thuspreventing the lead from forming deposits in the engine. The lead prevents premature burningof the gas/air mixture in the engine’s cylinders that causes the “knocking” sound in the engine.The lead combines with the bromine to form lead bromide, a volatile gas, which is expelledthrough the car’s exhaust system. Ethylene dibromide is a potent carcinogen. Since the introductionof lead free gasoline, this use has declined in importance; recently, other chemicalshave been substituted for the lead as an additive in gasoline.
Methyl bromide is used as a pesticide, which is very effective against parasitic nematodes(e.g., hookworms). Silver bromide is used in photography. Compounds of bromide are usedas flame-retardants, water purifiers, dyes, and pharmaceuticals. Bromine has many applicationswhen it is combined with organic compounds. For example, it is used as a reagent tostudy the organic reactions of many other compounds. It is also used as a disinfectant, afumigant, and a sedative. In the nineteenth century, many people took a “bromide” to easetension.
Uses
Bromine is used for bleaching fibers and silk,as a disinfectant for purifying water, in themanufacture of bromo compounds for dyesand pharmaceutical uses, as an analyticalreagent, and in organic synthesis. It occursin igneous rock and seawater.
Uses
manufacture of organic and inorganic chemicals, such as fuel additives, fire retardants, pesticides, oil well drilling fluids, pharmaceuticals, dyestuffs. In water disinfection; as bleaching agent, surface disinfectant.
Flammability and Explosibility
Bromine alone is a noncombustible substance (NFPA rating = 0).
storage
work with bromine should be conducted in a
fume hood to prevent exposure by inhalation, and splash goggles and rubber gloves
should be worn at all times when handling this corrosive substance. Containers of
bromine should be stored at room temperature in a secondary container separately
from readily oxidizable substances.
Purification Methods
Reflux the brown liquid with solid KBr and distil, then dry the distillate by shaking it with an equal volume of conc H2SO4, then redistil it. The H2SO4 treatment can be replaced by direct distillation from BaO or P2O5 A more extensive purification [Hildenbrand et al. J Am Chem Soc 80 4129 1958] is to reflux about 1L of bromine for 1hour with a mixture of 16g of CrO3 in 200mL of conc H2SO4 (to remove organic material). The bromine is distilled into a clean, dry, glass-stoppered bottle, and chlorine is removed by dissolving ca 25g of freshly fused CsBr in 500mL of the bromine and standing overnight. To remove HBr and water, the bromine is then distilled back and forth through a train containing alternate tubes of MgO and P2O5. [Schmeisser in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 275 1963.] HIGHLY TOXIC.
