It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. A measure of how difficult it is to deform a material. It is given by the ratio of the shear stress to the shear strain.
A measure of how difficult it is to compress a substance. It is given by the ratio of the pressure on a body to the fractional decrease in volume.
A measure of the propensity of a substance to evaporate. It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site. Copyright of and ownership in the Images reside with Murray Robertson.
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Nor shall the RSC be in any event liable for any damage to your computer equipment or software which may occur on account of your access to or use of the Site, or your downloading of materials, data, text, software, or images from the Site, whether caused by a virus, bug or otherwise. Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes.
Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements. Appearance The description of the element in its natural form.
Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially.
Uses and properties. Image explanation. The image intends to reflect the rich colour, liquidity and aromatic nature of the element. Bromine is a deep-red, oily liquid with a sharp smell.
It is toxic. Bromine is used in many areas such as agricultural chemicals, dyestuffs, insecticides, pharmaceuticals and chemical intermediates.
Some uses are being phased out for environmental reasons, but new uses continue to be found. Bromine compounds can be used as flame retardants. They are added to furniture foam, plastic casings for electronics and textiles to make them less flammable. However, the use of bromine as a flame retardant has been phased out in the USA because of toxicity concerns.
Organobromides are used in halon fire extinguishers that are used to fight fires in places like museums, aeroplanes and tanks. Silver bromide is a chemical used in film photography. Before leaded fuels were phased out, bromine was used to prepare 1,2-di-bromoethane, which was an anti-knock agent. Biological role. Bromine is present in small amounts, as bromide, in all living things. However, it has no known biological role in humans. Bromine has an irritating effect on the eyes and throat, and produces painful sores when in contact with the skin.
Natural abundance. Bromine is extracted by electrolysis from natural bromine-rich brine deposits in the USA, Israel and China. It was the first element to be extracted from seawater, but this is now only economically viable at the Dead Sea, Israel, which is particularly rich in bromide up to 0.
Help text not available for this section currently. Elements and Periodic Table History. He took the concentrated residue which remained after most of the brine had evaporated and passed chlorine gas into it. In so doing he liberated an orange-red liquid which he deduced was a new element. He was asked to produce more of it, and while he was doing so Balard published his results and so became known at its discoverer.
Atomic data. Bond enthalpies. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom.
Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk.
Relative supply risk 7 Crustal abundance ppm 0. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate.
Pressure and temperature data — advanced. Listen to Bromine Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. Hello, welcome to Chemistry in its element where this week we're sniffing out the chemical that is named after the Greek word for stench and this substance has certainly kicked up a stink in its own right in its time because it makes holes in the ozone layer.
But Laura Syrett says the industry also labours under another problem - "chemophobia". As an example she cites brominated vegetable oil or BVO , which was commonly added as an emulsifier in soft drinks such as Fanta and Gatorade. Without BVO or a substitute, the orange colour would gravitate to the bottom of your bottle, leaving the top half clear.
Something similar would happen to the flavour. The list included BVO - banned in the EU and Japan - which it claimed was "linked to major organ system damage, birth defects, growth problems, schizophrenia, and hearing loss".
Nonetheless, a petition on Change. Was the campaign against BVO rational? The chemistry blogger Derek Lowe points out that the few people known to have suffered health problems none of which were quite like those listed by Buzzfeed were drinking a vast amount of BVO-containing drinks - in the order of two to four litres per day. Another controversial case, according to Laura Syrett, is connected with fracking. In , tests of drinking water wells in Pennsylvania found increased levels of bromide salts - the same kind of stuff that supposedly makes people prefer an early night with a hot water bottle - linked to fracking activity at the Marcellus shale deposit.
Bromide salts are widely used in oil and gas drilling. Being near the bottom of the periodic table, bromine atoms are heavy. Dissolve its salts in water and you get an exceptionally heavy brine that can be used to stabilise high pressure wells and stop them collapsing.
In the end, an error was found in the Marcellus tests - in reality only one well showed elevated bromide levels, not seven as originally reported. One case, Syrett suggests, is a long way from proving a causal connection. Meanwhile, she points out, tourists are happy to come and bathe in the Dead Sea, with the world's highest concentration of bromide at 0.
The criticisms sting for an industry that feels it is actually doing a lot of good for the world. Besides fire retardants, one of the biggest new uses of bromine is in capturing mercury in the coal burned in power stations - in much the same way that it used to capture lead in the petrol burned in your car engine, except that this time it actually helps to stop the emission of a poisonous metal into the air.
As Anat laments: "The bromine industry has not done a very good job in PR, in educating people that there are chemicals there that save your life and keep you safe. It certainly does not help that so many of the chemicals they produce have such terrifyingly long and alien names… polybrominated diphenyl ether and hexabromocyclododecane, for example.
To put it another way, who would drink coffee if they knew it contained 1,3,7-Trimethylpurine-2,6-dione caffeine? Especially if you added a spoonful of 2R,3R,4S,5S,6R [ 2S,3S,4S,5R -3,4-dihydroxy-2,5-bis hydroxymethyl oxapentyl]oxy hydroxymethyl oxahexane-3,4,5-triol - better known as sugar?
Image source, Science Photo Library. Bromine saves lives, they point out. Image source, Google. Image source, ICL. So what's the problem with these products? Image source, Getty Images. Bromine is soluble in organic solvents and in water. Bromine is used in industry to make organobromo compounds. A major one was dibromoethane an agent for leaded gasoline, before they were largely phased out due to environmental considerations.
Other organobromines are used as insecticides, in fire extinguishers and to make pharmaceuticals. Bromine is used in making fumigants, dyes, flameproofing agents, water purification compounds, sanitizes, medicinals, agents for photography and in brominates vegetable oil, used as emulsifier in many citrus-flavoured solft drinks. Bromine is a naturally occurring element that can be found in many inorganic substances. Humans however, have many years ago started the introduction of organic bromines in the environment.
These are all compounds that are not natural and can cause serious harm to human health and the environment. In diffuse crustal rock bromine naturally occurs as bromide salts. Bromine salts have accumulated in sea water 85 ppm , from which bromine is extracted.
World production of bromine is more than In this last case it is extracted from sea water at a plant on the coast of Anglesey, Wales. Bromine is corrosive to human tissue in a liquid state and its vapors irritate eyes and throat. Bromine vapors are very toxic with inhalation. Humans can absorb organic bromines through the skin, with food and during breathing. Organic bromines are widely used as sprays to kill insects and other unwanted pests.
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