Atomic Number: 12 Period Number: 3 Group Number: 2
Magnesium is an alkaline earth metal and it ranks No. 4 in the earth as a whole. It is very active and no free element is found until now. Magnesium is also crucial to human's body. There are three stable isotopes in nature: 24Mg, 25Mg and 26Mg. Among them, 24Mg occupies 79%. Most Magnesium are found in only dolomite, magnesite, brucite, carnallite, talc, and olivine.
Magnesium is a commercially important metal with many uses. It is only two thirds as dense as aluminum. It is easily machined, cast, forged, and welded. It is used extensively in alloys, chiefly with aluminum and zinc, and with manganese. Magnesium alloys were used as early as 1910 in Germany. Early structural uses of magnesium alloys were in aircraft fuselages, engine parts, and wheels. They are now also used in jet-engine parts, rockets and missiles, luggage frames, portable power tools, and ameras and optical instruments. Duralumin and magnalium are alloys of magnesium. The metal is also used in pyrotechnics, especially in incendiary bombs, signals, and flares, and as a fuse for thermite. It is used in photographic flashbulbs and is added to some rocket and missile fuels. An important use is in preventing the corrosion of iron and steel, as in pipelines and ship bottoms. For this purpose a magnesium plate is connected electrically to the iron. The rapid oxidation of the magnesium prevents the slower oxidation and corrosion of the iron.
Magnesium forms many compounds. The oxide, hydroxide, chloride, carbonate, and sulfate are commercially important. They are used in ceramics, cosmetics, fertilizers, insulation, leather tanning, and textile processing. Epsom salts (magnesium sulfate heptahydrate (MgSO4·7H2O), milk of magnesia (magnesium hydroxide, Mg(OH)2), and citrate of magnesia are used in medicine. Magnesium reacts with organic halides to form the Grignard reagents of organic chemistry.
Physical and Chemical Properties:
Atomic Weight: 24.3050
Melting Point: 923 K
Boiling Point: 1363 K
Density: 1.74 g/cm3
Phase at Room Temperature: Solid
Element Classification: Metal
Ionization Energy: 7.646 eV
Oxidation State: +2
Wikipedia - Basics on Magnesium
WebElements - The basic elements of Magnesium
Jefferson Lab - Learning about Magnesium