Magnesium
Atomic Number: 12
Symbol: Mg
Atomic Weight: 24.305
Discovery: Recognized as an element by Black 1775; Isolated by Sir Humphrey Davy 1808 (England)
Electron Configuration: [Ne] 3s2
Word Origin: Magnesia, a district in Thessaly, Greece
Properties: Magnesium has a melting point of 648.8°C, boiling point of 1090°C, specific gravity of 1.738 (20°C), and valence of 2. Magnesium metal is light (one-third lighter than aluminum), silvery-white, and relatively tough. The metal tarnishes slightly in air. Finely divided magnesium ignites upon heating in air, burning with a bright white flame.
Uses: Magnesium is used in pyrotechnic and incendiary devices. It is alloyed with other metals to make them lighter and more easily welded, with applications in the aerospace industry. Magnesium is added to many propellents. It is used as a reducing agent in the preparation of uranium and other metals that are purified from their salts. Magnesite is used in refactories. Magnesium hydroxide (milk of magnesia), sulfate (Epsom salts), chloride, and citrate are used in medicine. Organic magnesium compounds have many uses. Magnesium is essential for plant and animal nutrition. Chlorophyll is a magnesium-centered porphyrin.
Sources: Magnesium is the 8th most abundant element in the earth's crust. While it is not found free it nature, it is available in minerals including magnesite and dolomite. The metal may be obtained by electrolysis of fused magnesium chloride derived from brines and seawater.
Atomic Weight: 24.305
Element Classification: Alkaline Earth Metal
Density (g/cc): 1.738
Appearance: lightweight, malleable, silvery-white metal
Atomic Radius (pm): 160
Atomic Volume (cc/mol): 14.0
Covalent Radius (pm): 136
Ionic Radius: 66 (+2e)
Specific Heat (@20°C J/g mol): 1.025
Fusion Heat (kJ/mol): 9.20
Evaporation Heat (kJ/mol): 131.8
Debye Temperature (K): 318.00
Pauling Negativity Number: 1.31
First Ionizing Energy (kJ/mol): 737.3
Oxidation States: 2
Lattice Structure: Hexagonal
Lattice Constant (Å): 3.210
Lattice C/A Ratio: 1.624
References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Lange's Handbook of Chemistry (1952), CRC Handbook of Chemistry & Physics (18th Ed.)
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