Data for this section been provided by the British Geological Survey. An integrated supply risk index from 1 very low risk to 10 very high risk. This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores.
The percentage of a commodity which is recycled. A higher recycling rate may reduce risk to supply. The availability of suitable substitutes for a given commodity. The percentage of an element produced in the top producing country. The higher the value, the larger risk there is to supply. The percentage of the world reserves located in the country with the largest reserves. A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K. A measure of the stiffness of a substance. 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.
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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 is inspired by chlorophyll, the molecule contained in green plants that enables them to photosynthesise. Chlorophyll contains a single atom of magnesium at its centre. A silvery-white metal that ignites easily in air and burns with a bright light. Magnesium is one-third less dense than aluminium. It improves the mechanical, fabrication and welding characteristics of aluminium when used as an alloying agent.
These alloys are useful in aeroplane and car construction. Magnesium is used in products that benefit from being lightweight, such as car seats, luggage, laptops, cameras and power tools.
It is also added to molten iron and steel to remove sulfur. Magnesium sulfate is sometimes used as a mordant for dyes. Magnesium hydroxide is added to plastics to make them fire retardant.
Magnesium oxide is used to make heat-resistant bricks for fireplaces and furnaces. It is also added to cattle feed and fertilisers. Magnesium hydroxide milk of magnesia , sulfate Epsom salts , chloride and citrate are all used in medicine.
Grignard reagents are organic magnesium compounds that are important for the chemical industry. Biological role. Magnesium is an essential element in both plant and animal life.
Chlorophyll is the chemical that allows plants to capture sunlight, and photosynthesis to take place. Chlorophyll is a magnesium-centred porphyrin complex. Without magnesium photosynthesis could not take place, and life as we know it would not exist.
In humans, magnesium is essential to the working of hundreds of enzymes. Humans take in about — milligrams of magnesium each day. We each store about 20 grams in our bodies, mainly in the bones. Natural abundance. It is found in large deposits in minerals such as magnesite and dolomite. The sea contains trillions of tonnes of magnesium, and this is the source of much of the , tonnes now produced each year.
It is prepared by reducing magnesium oxide with silicon, or by the electrolysis of molten magnesium chloride. Help text not available for this section currently. Elements and Periodic Table History. The first person to recognise that magnesium was an element was Joseph Black at Edinburgh in He distinguished magnesia magnesium oxide, MgO from lime calcium oxide, CaO although both were produced by heating similar kinds of carbonate rocks, magnesite and limestone respectively.
Another magnesium mineral called meerschaum magnesium silicate was reported by Thomas Henry in , who said that it was much used in Turkey to make pipes for smoking tobacco.
An impure form of metallic magnesium was first produced in by Anton Rupprecht who heated magnesia with charcoal. A pure, but tiny, amount of the metal was isolated in by Humphry Davy by the electrolysis of magnesium oxide.
However, it was the French scientist, Antoine-Alexandre-Brutus Bussy who made a sizeable amount of the metal in by reacting magnesium chloride with potassium, and he then studied its properties. Atomic data. Nov 12, Explanation: Z refers to the number of nuclear protons. Related questions How do you find mass number of an isotope?
What does the difference between the mass number and the atomic number tell us? Why is mass number a decimal? What type of radioactive decay produces no change in mass number? How is the mass number written? What is the nucleon number? Crawford said that additional measurements and theory work on Mg, and that nearby isotopes could help to positively identify the shape of the Mg nucleus, and to explain what is causing the change in nuclear structure.
Note: Content may be edited for style and length. Science News. Journal Reference : H. Crawford, P. Fallon, A. Macchiavelli, P. Doornenbal, N. Aoi, F. Browne, C. Campbell, S. Chen, R. Clark, M. Cromaz, E. Ideguchi, M. Jones, R. Kanungo, M. MacCormick, S. Momiyama, I. Murray, M.
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