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. 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. 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 Magnesium 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, this week we meet the substance whose chemical claim to fame is that its quite literally hit a bum note in the past as a cure for constipation. But its explosive role isn't just confined to the colon because it's also the basis of incendriary bombs and even the existence of life on earth. And to tell the story of Magnesium, here's John Emsley. The summer of saw England gripped by drought, but as Henry Wicker walked across Epsom Common he was came across a pool of water from which thirsty cattle refused to drink.
He found that the water tasted bitter and on evaporation it yielded a salt which had a remarkable effect: it acted as a laxative. This became the famous Epsom's salt magnesium sulfate, MgSO 4 and became a treatment for constipation for the next years. The first person to propose that magnesium was an element was Joseph Black of Edinburgh in , and an impure form of metallic magnesium was produced in by Anton Rupprecht who heated magnesia magnesium oxide, MgO with charcoal.
He named the element austrium after his native Austria. A small sample of the pure metal was isolated by Humphry Davy in , by the electrolysis of moist MgO, and he proposed the name magnium based on the mineral magnesite MgCO 3 which came from Magnesia in Greece.
Neither name survived and eventually it was called magnesium. Magnesium is essential to almost all life on Earth - it is at the heart of the chlorophyll molecule, which plants use to convert carbon dioxide into glucose, and then to cellulose, starch, and many other molecules which pass along the food chain. Humans take in around mg of magnesium per day and we need at least mg, but the body has a store of around 25 g of this element in its skeleton so there is rarely a deficiency.
Almonds, brazil nuts, cashew nuts, soybeans, parsnips, bran, and even chocolate are all rich in magnesium. Some brands of beer contain a lot, such as Webster's Yorkshire Bitter - it may owe some of its flavour to the high levels of magnesium sulfate in the water used to brew it.
Magnesium is the seventh most abundant element in the Earth's crust, and third most abundant if the Earth's mantle is also taken into consideration because this consists largely of olivine and pyroxene, which are magnesium silicates.
It is also abundant in sea water p. The metal itself was produced by the electrolysis of the molten chloride. Once magnesium starts to burn it is almost impossible to extinguish, because it reacts exothermically with oxygen, nitrogen and water. It burns with a bright light and was used for photographic flash bulbs It made an ideal incendiary agent and in some air raids during World War II as many as half a million 2 kg magnesium bombs would be scattered over a city in the space of an hour.
The result was massive conflagrations and firestorms. Bulk magnesium metal is not easily ignited so this had to be done by a thermite reaction at the heart of the bomb. The thermite reaction, between aluminium powder and iron oxide, releases more than enough heat to cause the magnesium casing of the bomb to burn fiercely. Many minerals are known which contain magnesium; but the main ones are dolomite calcium magnesium carbonate, CaMg CO 3 2 and magnesite which are mined to the extent of 10 million tonnes per year.
Magnesite is heated to convert it to magnesia MgO , and this has several applications: fertilizers; cattle feed supplement; a bulking agent in plastics; and for heat-resistant bricks for fireplaces and furnaces. The metal itself is being produced in increasing amounts.
It was originally introduced for racing bicycles which were the first vehicles to use pure magnesium frames, giving a better combination of strength and lightness than other metals. A steel frame is nearly five times heavier than a magnesium one.
For use as a metal, magnesium is alloyed with a few percent of aluminium, plus traces of zinc and manganese, to improve strength, corrosion resistance and welding qualities, and this alloy is used to save energy by making things lighter.
Magnesium is an unusual metal in that it is difficult to ignite when there is a chunk of it, but when it is burning, it is very hard to extinguish. It continues to burn in nitrogen, carbon dioxide and even in water! On the other hand, magnesium powder and shavings are easy to ignite. When it burns, it gives off a brilliant white light. Magnesium powder was used as flash powder in the early days of photography.
Now it is used in fireworks and marine flares. Outdoors enthusiasts often carry small blocks of magnesium — which they shave — to start their fires. Magnesium is the fourth most common element in the Earth after iron, oxygen and silicon. In its purest form, magnesium is comparable to aluminium. It is strong and lightweight, making it useful for manufacturing automotive components. Magnesium alloys are becoming more common in the aerospace industry as the need for lightweight fuel-efficient aircraft grows.
Magnesium is vital for photosynthesis in plants. In fact, a magnesium atom forms the centre of every chlorophyll molecule. Plants use magnesium for other life processes too. Plants get their magnesium from the soil. It is often a macroelement in fertilisers.
Like plants, animals require magnesium for their cells to function. Animals obtain magnesium from their local environment. Ruminants — cows and to a lesser extent sheep and goats — require magnesium supplements to reduce the risk of milk fever and grass staggers. Milk fever is most often linked with calving and birth — milk and colostrum production removes calcium from the blood.
Magnesium compounds are used as refractory material in furnace linings for producing metals iron and steel, nonferrous metals , glass, and cement. It also has many useful chemical and metallurgic properties, which make it appropriate for many other non-structural applications. Magnesium components are widely used in industry and agriculture.
Other uses include: removal of sulphur form iron and steel, photoengraved plates in the printing industry; reducing agent for the production of pure uranium and other metals from their salts; flashlight photography, flares, and pyrotechnics. Dolomite and magnesite are mined to the extent of 10 million tonnes per year, in countries such as China, Turkey, North Korea, Slovakia, Austria, Russia and Greece.
There is no evidence that magnesium produces systemic poisoning although persistent over-indulgence in taking magnesium supplements and medicines can lead to muscule weakness, lethargy and confusion.
Inhalation: dust may irritate mucous membranes or upper respiratory tract. Eyes: mechanical injury or particle may embed in eye. Viewing of burning magnesium powder without fire glasses may result in "Welder's flash", due to intense white flame.
Skin: embedding of particle in skin. Ingestion: unlikely; however, ingestion of large amounts of magnesium powder could cause injury. Magnesium oxide fume is a by-product of burning magnesium. Physical dangers: Dust explosion possible if in powder or granular form, mixed with air. If dry, it can be charged electrostatically by swirling, pneumatic transport, pouring, etc. C hemical dangers: The substance may spontaneously ignite on contact with air or moisture producing irritating or toxic fumes.
Reacts violently with strong oxidants. Reacts violently with many substances causing fire and explosion hazard. Reacts with acids and water forming flammable hydrogen gas see ICSC , causing fire and explosion hazard.
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