Magnesium

  • magnesium, 12mg
    csiro scienceimage 2893 crystalised magnesium.jpg
    magnesium
    pronunciationm/ (nee-zee-əm)
    appearanceshiny grey solid
    standard atomic weight ar, std(mg)[24.30424.307] conventional: 24.305
    magnesium in the periodic table
    hydrogen helium
    lithium beryllium boron carbon nitrogen oxygen fluorine neon
    sodium magnesium aluminium silicon phosphorus sulfur chlorine argon
    potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
    rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon
    caesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury (element) thallium lead bismuth polonium astatine radon
    francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson
    be

    mg

    ca
    sodiummagnesiumaluminium
    atomic number (z)12
    groupgroup 2 (alkaline earth metals)
    periodperiod 3
    blocks-block
    element category  alkaline earth metal
    electron configuration[ne] 3s2
    electrons per shell2, 8, 2
    physical properties
    phase at stpsolid
    melting point923 k ​(650 °c, ​1202 °f)
    boiling point1363 k ​(1091 °c, ​1994 °f)
    density (near r.t.)1.738 g/cm3
    when liquid (at m.p.)1.584 g/cm3
    heat of fusion8.48 kj/mol
    heat of vaporization128 kj/mol
    molar heat capacity24.869[1] j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 701 773 861 971 1132 1361
    atomic properties
    oxidation states+1,[2] +2 (a strongly basic oxide)
    electronegativitypauling scale: 1.31
    ionization energies
    • 1st: 737.7 kj/mol
    • 2nd: 1450.7 kj/mol
    • 3rd: 7732.7 kj/mol
    • (more)
    atomic radiusempirical: 160 pm
    covalent radius141±7 pm
    van der waals radius173 pm
    color lines in a spectral range
    spectral lines of magnesium
    other properties
    natural occurrenceprimordial
    crystal structurehexagonal close-packed (hcp)
    hexagonal close packed crystal structure for magnesium
    speed of sound thin rod4940 m/s (at r.t.) (annealed)
    thermal expansion24.8[3] µm/(m·k) (at 25 °c)
    thermal conductivity156[4] w/(m·k)
    electrical resistivity43.9[5] nΩ·m (at 20 °c)
    magnetic orderingparamagnetic
    magnetic susceptibility+13.1·10−6 cm3/mol (298 k)[6]
    young's modulus45 gpa
    shear modulus17 gpa
    bulk modulus35.4[7] gpa
    poisson ratio0.290
    mohs hardness1–2.5
    brinell hardness44–260 mpa
    cas number7439-95-4
    history
    namingafter magnesia, greece[8]
    discoveryjoseph black (1755[8])
    first isolationhumphry davy (1808[8])
    main isotopes of magnesium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    24mg 79.0% stable
    25mg 10.0% stable
    26mg 11.0% stable
    category category: magnesium
    | references

    magnesium is a chemical element with the symbol mg and atomic number 12. it is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (group 2, or alkaline earth metals) of the periodic table: all group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure.

    magnesium is the ninth most abundant element in the universe.[9][10] it is produced in large, aging stars from 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 is the eighth most abundant element in the earth's crust[11] 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.[12]

    magnesium occurs naturally only in combination with other elements, where it invariably has a +2 oxidation state. the free element (metal) can be produced artificially, and is highly reactive (though in the atmosphere, it is soon coated in a thin layer of oxide that partly inhibits reactivity – see passivation). the free metal burns with a characteristic brilliant-white light. the metal is now obtained mainly by electrolysis of magnesium salts obtained from brine, and is used primarily as a component in aluminium-magnesium alloys, sometimes called magnalium or magnelium. magnesium is less dense than aluminium, and the alloy is prized for its combination of lightness and strength.

    magnesium is the eleventh most abundant element by mass in the human body and is essential to all cells and some 300 enzymes.[13] 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, antacids (e.g., milk of magnesia), and to stabilize abnormal nerve excitation or blood vessel spasm in such conditions as eclampsia.[13]

  • characteristics
  • forms
  • production
  • history
  • uses as a metal
  • useful compounds
  • biological roles
  • see also
  • references
  • cited sources
  • external links

Magnesium, 12Mg
CSIRO ScienceImage 2893 Crystalised magnesium.jpg
Magnesium
Pronunciationm/ (NEE-zee-əm)
Appearanceshiny grey solid
Standard atomic weight Ar, std(Mg)[24.30424.307] conventional: 24.305
Magnesium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Be

Mg

Ca
sodiummagnesiumaluminium
Atomic number (Z)12
Groupgroup 2 (alkaline earth metals)
Periodperiod 3
Blocks-block
Element category  Alkaline earth metal
Electron configuration[Ne] 3s2
Electrons per shell2, 8, 2
Physical properties
Phase at STPsolid
Melting point923 K ​(650 °C, ​1202 °F)
Boiling point1363 K ​(1091 °C, ​1994 °F)
Density (near r.t.)1.738 g/cm3
when liquid (at m.p.)1.584 g/cm3
Heat of fusion8.48 kJ/mol
Heat of vaporization128 kJ/mol
Molar heat capacity24.869[1] J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 701 773 861 971 1132 1361
Atomic properties
Oxidation states+1,[2] +2 (a strongly basic oxide)
ElectronegativityPauling scale: 1.31
Ionization energies
  • 1st: 737.7 kJ/mol
  • 2nd: 1450.7 kJ/mol
  • 3rd: 7732.7 kJ/mol
  • (more)
Atomic radiusempirical: 160 pm
Covalent radius141±7 pm
Van der Waals radius173 pm
Color lines in a spectral range
Spectral lines of magnesium
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for magnesium
Speed of sound thin rod4940 m/s (at r.t.) (annealed)
Thermal expansion24.8[3] µm/(m·K) (at 25 °C)
Thermal conductivity156[4] W/(m·K)
Electrical resistivity43.9[5] nΩ·m (at 20 °C)
Magnetic orderingparamagnetic
Magnetic susceptibility+13.1·10−6 cm3/mol (298 K)[6]
Young's modulus45 GPa
Shear modulus17 GPa
Bulk modulus35.4[7] GPa
Poisson ratio0.290
Mohs hardness1–2.5
Brinell hardness44–260 MPa
CAS Number7439-95-4
History
Namingafter Magnesia, Greece[8]
DiscoveryJoseph Black (1755[8])
First isolationHumphry Davy (1808[8])
Main isotopes of magnesium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
24Mg 79.0% stable
25Mg 10.0% stable
26Mg 11.0% stable
Category Category: Magnesium
| references

Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (group 2, or alkaline earth metals) of the periodic table: all group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure.

Magnesium is the ninth most abundant element in the universe.[9][10] It is produced in large, aging stars from 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 is the eighth most abundant element in the Earth's crust[11] 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.[12]

Magnesium occurs naturally only in combination with other elements, where it invariably has a +2 oxidation state. The free element (metal) can be produced artificially, and is highly reactive (though in the atmosphere, it is soon coated in a thin layer of oxide that partly inhibits reactivity – see passivation). The free metal burns with a characteristic brilliant-white light. The metal is now obtained mainly by electrolysis of magnesium salts obtained from brine, and is used primarily as a component in aluminium-magnesium alloys, sometimes called magnalium or magnelium. Magnesium is less dense than aluminium, and the alloy is prized for its combination of lightness and strength.

Magnesium is the eleventh most abundant element by mass in the human body and is essential to all cells and some 300 enzymes.[13] 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, antacids (e.g., milk of magnesia), and to stabilize abnormal nerve excitation or blood vessel spasm in such conditions as eclampsia.[13]