Cobalt

  • cobalt, 27co
    cobalt chips
    cobalt
    pronunciationt/ (about this soundlisten)[1]
    appearancehard lustrous bluish gray metal
    standard atomic weight ar, std(co)58.933194(3)[2]
    cobalt 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


    co

    rh
    ironcobaltnickel
    atomic number (z)27
    groupgroup 9
    periodperiod 4
    blockd-block
    element category  transition metal
    electron configuration[ar] 3d7 4s2
    electrons per shell2, 8, 15, 2
    physical properties
    phase at stpsolid
    melting point1768 k ​(1495 °c, ​2723 °f)
    boiling point3200 k ​(2927 °c, ​5301 °f)
    density (near r.t.)8.90 g/cm3
    when liquid (at m.p.)8.86 g/cm3
    heat of fusion16.06 kj/mol
    heat of vaporization377 kj/mol
    molar heat capacity24.81 j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 1790 1960 2165 2423 2755 3198
    atomic properties
    oxidation states−3, −1, 0, +1, +2, +3, +4, +5[3] (an amphoteric oxide)
    electronegativitypauling scale: 1.88
    ionization energies
    • 1st: 760.4 kj/mol
    • 2nd: 1648 kj/mol
    • 3rd: 3232 kj/mol
    • (more)
    atomic radiusempirical: 125 pm
    covalent radiuslow spin: 126±3 pm
    high spin: 150±7 pm
    color lines in a spectral range
    spectral lines of cobalt
    other properties
    natural occurrenceprimordial
    crystal structurehexagonal close-packed (hcp)
    hexagonal close packed crystal structure for cobalt
    speed of sound thin rod4720 m/s (at 20 °c)
    thermal expansion13.0 µm/(m·k) (at 25 °c)
    thermal conductivity100 w/(m·k)
    electrical resistivity62.4 nΩ·m (at 20 °c)
    magnetic orderingferromagnetic
    young's modulus209 gpa
    shear modulus75 gpa
    bulk modulus180 gpa
    poisson ratio0.31
    mohs hardness5.0
    vickers hardness1043 mpa
    brinell hardness470–3000 mpa
    cas number7440-48-4
    history
    discovery and first isolationgeorg brandt (1735)
    main isotopes of cobalt
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    56co syn 77.27 d ε 56fe
    57co syn 271.79 d ε 57fe
    58co syn 70.86 d ε 58fe
    59co 100% stable
    60co syn 5.2714 y β, γ 60ni
    category category: cobalt
    | references

    cobalt is a chemical element with the symbol co and atomic number 27. like nickel, cobalt is found in the earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. the free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.

    cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was later thought to be due to the known metal bismuth. miners had long used the name kobold ore (german for goblin ore) for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. in 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the kobold.

    today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as cobaltite (coass). the element is, however, more usually produced as a by-product of copper and nickel mining. the copper belt in the democratic republic of the congo (drc) and zambia yields most of the global cobalt production. world production in 2016 was 116,000 tonnes (according to natural resources canada), and the drc alone accounted for more than 50%.[4]

    cobalt is primarily used in lithium-ion batteries, and in the manufacture of magnetic, wear-resistant and high-strength alloys. the compounds cobalt silicate and cobalt(ii) aluminate (coal2o4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. cobalt occurs naturally as only one stable isotope, cobalt-59. cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays.

    cobalt is the active center of a group of coenzymes called cobalamins. vitamin b12, the best-known example of the type, is an essential vitamin for all animals. cobalt in inorganic form is also a micronutrient for bacteria, algae, and fungi.

  • characteristics
  • compounds
  • isotopes
  • history
  • occurrence
  • production
  • extraction
  • applications
  • biological role
  • health issues
  • see also
  • references
  • further reading
  • external links

Cobalt, 27Co
cobalt chips
Cobalt
Pronunciationt/ (About this soundlisten)[1]
Appearancehard lustrous bluish gray metal
Standard atomic weight Ar, std(Co)58.933194(3)[2]
Cobalt 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


Co

Rh
ironcobaltnickel
Atomic number (Z)27
Groupgroup 9
Periodperiod 4
Blockd-block
Element category  Transition metal
Electron configuration[Ar] 3d7 4s2
Electrons per shell2, 8, 15, 2
Physical properties
Phase at STPsolid
Melting point1768 K ​(1495 °C, ​2723 °F)
Boiling point3200 K ​(2927 °C, ​5301 °F)
Density (near r.t.)8.90 g/cm3
when liquid (at m.p.)8.86 g/cm3
Heat of fusion16.06 kJ/mol
Heat of vaporization377 kJ/mol
Molar heat capacity24.81 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1790 1960 2165 2423 2755 3198
Atomic properties
Oxidation states−3, −1, 0, +1, +2, +3, +4, +5[3] (an amphoteric oxide)
ElectronegativityPauling scale: 1.88
Ionization energies
  • 1st: 760.4 kJ/mol
  • 2nd: 1648 kJ/mol
  • 3rd: 3232 kJ/mol
  • (more)
Atomic radiusempirical: 125 pm
Covalent radiusLow spin: 126±3 pm
High spin: 150±7 pm
Color lines in a spectral range
Spectral lines of cobalt
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for cobalt
Speed of sound thin rod4720 m/s (at 20 °C)
Thermal expansion13.0 µm/(m·K) (at 25 °C)
Thermal conductivity100 W/(m·K)
Electrical resistivity62.4 nΩ·m (at 20 °C)
Magnetic orderingferromagnetic
Young's modulus209 GPa
Shear modulus75 GPa
Bulk modulus180 GPa
Poisson ratio0.31
Mohs hardness5.0
Vickers hardness1043 MPa
Brinell hardness470–3000 MPa
CAS Number7440-48-4
History
Discovery and first isolationGeorg Brandt (1735)
Main isotopes of cobalt
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
56Co syn 77.27 d ε 56Fe
57Co syn 271.79 d ε 57Fe
58Co syn 70.86 d ε 58Fe
59Co 100% stable
60Co syn 5.2714 y β, γ 60Ni
Category Category: Cobalt
| references

Cobalt is a chemical element with the symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.

Cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was later thought to be due to the known metal bismuth. Miners had long used the name kobold ore (German for goblin ore) for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the kobold.

Today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as cobaltite (CoAsS). The element is, however, more usually produced as a by-product of copper and nickel mining. The copper belt in the Democratic Republic of the Congo (DRC) and Zambia yields most of the global cobalt production. World production in 2016 was 116,000 tonnes (according to Natural Resources Canada), and the DRC alone accounted for more than 50%.[4]

Cobalt is primarily used in lithium-ion batteries, and in the manufacture of magnetic, wear-resistant and high-strength alloys. The compounds cobalt silicate and cobalt(II) aluminate (CoAl2O4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays.

Cobalt is the active center of a group of coenzymes called cobalamins. Vitamin B12, the best-known example of the type, is an essential vitamin for all animals. Cobalt in inorganic form is also a micronutrient for bacteria, algae, and fungi.