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36-406: Physically the device is notable for its size and thinness. Available in both black and white colours, it has a Magnesium alloy casing, while its main feature is a 4.1-inch 480 x 800 pixel touchscreen. It only has two buttons, at the bottom of the screen. These are surface click buttons used for Home and Back functions. Other features include a rear-mounted 3.2MP autofocus camera. Another feature of

72-498: A half-life of 717,000 years. Excessive quantities of stable Mg have been observed in the Ca-Al-rich inclusions of some carbonaceous chondrite meteorites . This anomalous abundance is attributed to the decay of its parent Al in the inclusions, and researchers conclude that such meteorites were formed in the solar nebula before the Al had decayed. These are among

108-493: A magnesium-based engine . Magnesium also reacts exothermically with most acids such as hydrochloric acid (HCl), producing magnesium chloride and hydrogen gas, similar to the HCl reaction with aluminium, zinc, and many other metals. Although it is difficult to ignite in mass or bulk, magnesium metal will ignite. Magnesium may also be used as an igniter for thermite , a mixture of aluminium and iron oxide powder that ignites only at

144-531: A common reservoir. Magnesium is the eighth-most-abundant element in the Earth's crust by mass and tied in seventh place with iron in molarity . It is found in large deposits of magnesite , dolomite , and other minerals , and in mineral waters, where magnesium ion is soluble. Although magnesium is found in more than 60 minerals , only dolomite , magnesite , brucite , carnallite , talc , and olivine are of commercial importance. The Mg cation

180-510: A high purity product is easily achievable. China is almost completely reliant on the silicothermic Pidgeon process . Besides the Pigeon process, the second most used process for magnesium production is electrolysis . This is a two step process. The first step is to prepare feedstock containing magnesium chloride and the second step is to dissociate the compound in electrolytic cells as magnesium metal and chlorine gas . The basic reaction

216-429: A solid solution with calcium oxide by calcining the mineral dolomite , which is a solid solution of calcium and magnesium carbonates: Reduction occurs at high temperatures with silicon. A ferrosilicon alloy is used rather than pure silicon as it is more economical. The iron component has no bearing on the reaction, having the simplified equation: The calcium oxide combines with silicon as the oxygen scavenger, yielding

252-545: A variety of compounds important to industry and biology, including magnesium carbonate , magnesium chloride , magnesium citrate , magnesium hydroxide (milk of magnesia), magnesium oxide , magnesium sulfate , and magnesium sulfate heptahydrate ( Epsom salts ). As recently as 2020, magnesium hydride was under investigation as a way to store hydrogen. Magnesium has three stable isotopes : Mg , Mg and Mg . All are present in significant amounts in nature (see table of isotopes above). About 79% of Mg

288-408: A very high temperature. Organomagnesium compounds are widespread in organic chemistry . They are commonly found as Grignard reagents , formed by reaction of magnesium with haloalkanes . Examples of Grignard reagents are phenylmagnesium bromide and ethylmagnesium bromide . The Grignard reagents function as a common nucleophile , attacking the electrophilic group such as the carbon atom that

324-438: Is Mg . The isotope Mg is radioactive and in the 1950s to 1970s was produced by several nuclear power plants for use in scientific experiments. This isotope has a relatively short half-life (21 hours) and its use was limited by shipping times. The nuclide Mg has found application in isotopic geology , similar to that of aluminium. Mg is a radiogenic daughter product of Al , which has

360-658: Is a gray-white lightweight metal, two-thirds the density of aluminium. Magnesium has the lowest melting (923 K (650 °C)) and the lowest boiling point (1,363 K (1,090 °C)) of all the alkaline earth metals. Pure polycrystalline magnesium is brittle and easily fractures along shear bands . It becomes much more malleable when alloyed with small amounts of other metals, such as 1% aluminium. The malleability of polycrystalline magnesium can also be significantly improved by reducing its grain size to about 1  μm or less. When finely powdered, magnesium reacts with water to produce hydrogen gas: However, this reaction

396-486: Is a liquid metal. At the YSZ/liquid metal anode O is oxidized. A layer of graphite borders the liquid metal anode, and at this interface carbon and oxygen react to form carbon monoxide. When silver is used as the liquid metal anode, there is no reductant carbon or hydrogen needed, and only oxygen gas is evolved at the anode. It was reported in 2011 that this method provides a 40% reduction in cost per pound over

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432-585: Is as follows: The temperatures at which this reaction is operated is between 680 and 750 °C. The magnesium chloride can be obtained using the Dow process , a process that mixes sea water and dolomite in a flocculator or by dehydration of magnesium chloride brines. The electrolytic cells are partially submerged in a molten salt electrolyte to which the produced magnesium chloride is added in concentrations between 6-18%. This process does have its share of disadvantages including production of harmful chlorine gas and

468-425: Is essential to all cells and some 300 enzymes . Magnesium ions interact with polyphosphate compounds such as ATP , DNA , and RNA . Hundreds of enzymes require magnesium ions to function. Magnesium compounds are used medicinally as common laxatives and antacids (such as milk of magnesia ), and to stabilize abnormal nerve excitation or blood vessel spasm in such conditions as eclampsia . Elemental magnesium

504-482: Is first treated with lime (calcium oxide) and the precipitated magnesium hydroxide is collected: The hydroxide is then converted to magnesium chloride by treatment with hydrochloric acid and heating of the product to eliminate water: The salt is then electrolyzed in the molten state. At the cathode , the Mg ion is reduced by two electrons to magnesium metal: At the anode , each pair of Cl ions

540-426: Is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium. In the cosmos , magnesium is produced in large, aging stars by the sequential addition of three helium nuclei to a carbon nucleus. When such stars explode as supernovas , much of the magnesium is expelled into the interstellar medium where it may recycle into new star systems. Magnesium

576-441: Is much less dramatic than the reactions of the alkali metals with water, because the magnesium hydroxide builds up on the surface of the magnesium metal and inhibits further reaction. The principal property of magnesium metal is its reducing power. One hint is that it tarnishes slightly when exposed to air, although, unlike the heavier alkaline earth metals , an oxygen-free environment is unnecessary for storage because magnesium

612-401: Is oxidized to chlorine gas, releasing two electrons to complete the circuit: The carbothermic route to magnesium has been recognized as a low energy, yet high productivity path to magnesium extraction. The chemistry is as follows: C + MgO → CO + Mg A disadvantage of this method is that slow cooling the vapour can cause the reaction to quickly revert. To prevent this from happening,

648-514: Is present within the polar bond of a carbonyl group. A prominent organomagnesium reagent beyond Grignard reagents is magnesium anthracene , which is used as a source of highly active magnesium. The related butadiene -magnesium adduct serves as a source for the butadiene dianion. Complexes of dimagnesium(I) have been observed. The presence of magnesium ions can be detected by the addition of ammonium chloride , ammonium hydroxide and monosodium phosphate to an aqueous or dilute HCl solution of

684-447: Is protected by a thin layer of oxide that is fairly impermeable and difficult to remove. Direct reaction of magnesium with air or oxygen at ambient pressure forms only the "normal" oxide MgO. However, this oxide may be combined with hydrogen peroxide to form magnesium peroxide , MgO 2 , and at low temperature the peroxide may be further reacted with ozone to form magnesium superoxide Mg(O 2 ) 2 . Magnesium reacts with nitrogen in

720-458: Is the eighth most abundant element in the Earth's crust and the fourth most common element in the Earth (after iron , oxygen and silicon ), making up 13% of the planet's mass and a large fraction of the planet's mantle . It is the third most abundant element dissolved in seawater, after sodium and chlorine . This element is the eleventh most abundant element by mass in the human body and

756-541: Is the second-most-abundant cation in seawater (about 1 ⁄ 8 the mass of sodium ions in a given sample), which makes seawater and sea salt attractive commercial sources for Mg. To extract the magnesium, calcium hydroxide is added to the seawater to precipitate magnesium hydroxide . Magnesium hydroxide ( brucite ) is poorly soluble in water and can be collected by filtration. It reacts with hydrochloric acid to magnesium chloride . From magnesium chloride, electrolysis produces magnesium. World production

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792-407: The periodic table ) it occurs naturally only in combination with other elements and almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine . It

828-677: The TG01 is O2 Germany. It was thought that the device will be exclusively available through O2 throughout Europe, but this has transpired to not be true. The second one is NTT docomo , which is the Japanese largest operator. The TG-01 for NTT docomo is named as "docomo PRO series T-01A." In June or July 2009, it will be sold. In the UK the device is ranged by Orange. In late July 2009, the Federal Communications Commission of

864-531: The TG01 is its G-Sensor, which Toshiba claims enables gesture operations, such as shaking the TG01 to take a call or tilting it to switch between applications. It also has a custom user interface, which visually is demonstrated by three vertical stripes. Software features include the Internet Explorer Mobile 6 web browser, multimedia player, push email, and support for DivX and Flash for media playback. The first operator to announce deployment of

900-514: The United States passed the CDMA version of the TG01 for inspection, thus allowing the device to be sold in the United States. Magnesium Magnesium is a chemical element ; it has symbol   Mg and atomic number  12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of

936-573: The corrosion rate of magnesium in a salt solution by a factor of nearly ten. Magnesium's tendency to creep (gradually deform) at high temperatures is greatly reduced by alloying with zinc and rare-earth elements . Flammability is significantly reduced by a small amount of calcium in the alloy. By using rare-earth elements, it may be possible to manufacture magnesium alloys that are able to not catch fire at higher temperatures compared to magnesium's liquidus and in some cases potentially pushing it close to magnesium's boiling point. Magnesium forms

972-424: The magnesium can be dissolved directly in a suitable metal solvent before reversion starts happening. Rapid quenching of the vapour can also be performed to prevent reversion. A newer process, solid oxide membrane technology, involves the electrolytic reduction of MgO. At the cathode, Mg ion is reduced by two electrons to magnesium metal. The electrolyte is yttria-stabilized zirconia (YSZ). The anode

1008-540: The oldest objects in the Solar System and contain preserved information about its early history. It is conventional to plot Mg / Mg against an Al/Mg ratio. In an isochron dating plot, the Al/Mg ratio plotted is Al / Mg . The slope of the isochron has no age significance, but indicates the initial Al / Al ratio in the sample at the time when the systems were separated from

1044-619: The overall reaction being very energy intensive, creating environmental risks. The Pidgeon process is more advantageous regarding its simplicity, shorter construction period, low power consumption and overall good magnesium quality compared to the electrolysis method. In the United States, magnesium was once obtained principally with the Dow process in Corpus Christi TX , by electrolysis of fused magnesium chloride from brine and sea water . A saline solution containing Mg ions

1080-443: The quantity of these metals improves corrosion resistance. Sufficient manganese overcomes the corrosive effects of iron. This requires precise control over composition, increasing costs. Adding a cathodic poison captures atomic hydrogen within the structure of a metal. This prevents the formation of free hydrogen gas, an essential factor of corrosive chemical processes. The addition of about one in three hundred parts arsenic reduces

1116-455: The salt. The formation of a white precipitate indicates the presence of magnesium ions. Azo violet dye can also be used, turning deep blue in the presence of an alkaline solution of magnesium salt. The color is due to the adsorption of azo violet by Mg(OH) 2 . As of 2013, magnesium alloys consumption was less than one million tonnes per year, compared with 50 million tonnes of aluminium alloys . Their use has been historically limited by

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1152-530: The shores of the Great Salt Lake . In September 2021, China took steps to reduce production of magnesium as a result of a government initiative to reduce energy availability for manufacturing industries, leading to a significant price increase. The Pidgeon process and the Bolzano process are similar. In both, magnesium oxide is the precursor to magnesium metal. The magnesium oxide is produced as

1188-573: The solid state if it is powdered and heated to just below the melting point, forming Magnesium nitride Mg 3 N 2 . Magnesium reacts with water at room temperature, though it reacts much more slowly than calcium, a similar group 2 metal. When submerged in water, hydrogen bubbles form slowly on the surface of the metal; this reaction happens much more rapidly with powdered magnesium. The reaction also occurs faster with higher temperatures (see § Safety precautions ). Magnesium's reversible reaction with water can be harnessed to store energy and run

1224-403: The tendency of Mg alloys to corrode, creep at high temperatures, and combust. In magnesium alloys, the presence of iron , nickel , copper , or cobalt strongly activates corrosion . In more than trace amounts, these metals precipitate as intermetallic compounds , and the precipitate locales function as active cathodic sites that reduce water, causing the loss of magnesium. Controlling

1260-510: The very stable calcium silicate. The Mg/Ca ratio of the precursors can be adjusted by the addition of MgO or CaO. The Pidgeon and the Bolzano process differ in the details of the heating and the configuration of the reactor. Both generate gaseous Mg that is condensed and collected. The Pidgeon process dominates the worldwide production. The Pidgeon method is less technologically complex and because of distillation/vapour deposition conditions,

1296-626: Was approximately 1,100 kt in 2017, with the bulk being produced in China (930 kt) and Russia (60 kt). The United States was in the 20th century the major world supplier of this metal, supplying 45% of world production even as recently as 1995. Since the Chinese mastery of the Pidgeon process the US market share is at 7%, with a single US producer left as of 2013: US Magnesium, a Renco Group company located on

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