In such cases we would ask you to sign a Visual Elements licence agreement, tailored to the specific use you propose. The RSC makes no representations whatsoever about the suitability of the information contained in the documents and related graphics published on this Site for any purpose. All such documents and related graphics are provided "as is" without any representation or endorsement made and warranty of any kind, whether expressed or implied, including but not limited to the implied warranties of fitness for a particular purpose, non-infringement, compatibility, security and accuracy.
In no event shall the RSC be liable for any damages including, without limitation, indirect or consequential damages, or any damages whatsoever arising from use or loss of use, data or profits, whether in action of contract, negligence or other tortious action, arising out of or in connection with the use of the material available from this Site.
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. An image reflecting the importance of boron as an essential mineral for plants. Amorphous boron is used as a rocket fuel igniter and in pyrotechnic flares. It gives the flares a distinctive green colour. The most important compounds of boron are boric or boracic acid, borax sodium borate and boric oxide. These can be found in eye drops, mild antiseptics, washing powders and tile glazes. Borax used to be used to make bleach and as a food preservative.
Boric oxide is also commonly used in the manufacture of borosilicate glass Pyrex. It makes the glass tough and heat resistant. Fibreglass textiles and insulation are made from borosilcate glass. The isotope boron is good at absorbing neutrons. This means it can be used to regulate nuclear reactors. It also has a role in instruments used to detect neutrons. Biological role. Boron is essential for the cell walls of plants. We take in about 2 milligrams of boron each day from our food, and about 60 grams in a lifetime.
Some boron compounds are being studied as a possible treatment for brain tumours. Natural abundance. Boron occurs as an orthoboric acid in some volcanic spring waters, and as borates in the minerals borax and colemanite. Extensive borax deposits are found in Turkey. However, by far the most important source of boron is rasorite. High-purity boron is prepared by reducing boron trichloride or tribromide with hydrogen, on electrically heated filaments. Impure, or amorphous, boron can be prepared by heating the trioxide with magnesium powder.
Help text not available for this section currently. Elements and Periodic Table History. It was used as a flux used by goldsmiths. In fact, neither had produced the pure element which is almost impossible to obtain. A purer type of boron was isolated in by Henri Moissan. Eventually, E. Weintraub in the USA produced totally pure boron by sparking a mixture of boron chloride, BCl 3 vapour, and hydrogen. The material so obtained boron was found to have very different properties to those previously reported.
Atomic data. 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 4. When exposure to small amounts of boron takes place irritation of the nose, throat or eyes may occur. It takes 5 g of borc acid to make a person ill and 20 grams or more to put its life in danger. Eating fish or meat will not increase the boron concentrations in our bodies, as boron does not accumulate within the tissues of animals. Boron is an element that occurs in the environment mainly through natural processes. Boron occurs naturally in the environment due to the release into air, soil and water through weathering.
It may also occur in groundwater in very small amounts. Humans add boron by manufacturing glass, combusting coal, melting copper and through the addition of agricultural fertilizers. The concentrations of boron that are added by humans are smaller that the naturally added concentrations through natural weathering.
Boron exposure through air and drinking water is not very likely to occur, but the risk of exposure to borate dust in the workplace does exist. Boron exposure may also occur from consumer products such as cosmetics and laundry products.
Plants absorb boron from the ground and through plant-consuming animals it can end up in food chains. Borax sodium tetraborate forms naturally during the evaporation of some salt lakes, according to AZoM , an online reference site for the engineering and materials science community. In the eighth century A. These early uses echo in borax's and ultimately, boron's name: The word is from the Arabic "buraq," or white. However, the element itself was not extracted until , according to the Royal Society of Chemistry.
Even then, chemists weren't able to get a pure form of boron. That goal was not reached until a century later, in , when U. As part of borax, boron is a very common household element that is found in many detergents. Pro tip: A borax-sugar solution will also kill ants!
It's also in the recipe for the science-fair goop oobleck, a liquid with some very strange properties. A mixture of borax solution and liquid glue creates a substance that is liquid when it is poured but solid when it is under pressure. Oobleck is a non-Newtonian fluid , which means that its viscosity depends on the shear force applied to it. The glue and oobleck join up to create long, thin polymer molecules. A "tap" or strong pressure forces the molecules in the fluid together, creating a solid.
A slow movement like pouring or a gentle poke allows the molecules to flow against one another, making the oobleck behave like a fluid. Other boron compounds are used to make borosilicate glasses, enamels for covering steel and as a potential medicine for treating arthritis. Estimated Crustal Abundance : 1. Number of Stable Isotopes : 2 View all isotope data. Electron Shell Configuration :. Boron Previous Isotopes Next.
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