Niobium

  • niobium, 41nb
    a lump of gray shining crystals with hexagonal facetting
    niobium
    pronunciationm/ (oh-bee-əm)
    appearancegray metallic, bluish when oxidized
    standard atomic weight ar, std(nb)92.90637(1)[1]
    niobium 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
    v

    nb

    ta
    zirconiumniobiummolybdenum
    atomic number (z)41
    groupgroup 5
    periodperiod 5
    blockd-block
    element category  transition metal
    electron configuration[kr] 4d4 5s1
    electrons per shell2, 8, 18, 12, 1
    physical properties
    phase at stpsolid
    melting point2750 k ​(2477 °c, ​4491 °f)
    boiling point5017 k ​(4744 °c, ​8571 °f)
    density (near r.t.)8.57 g/cm3
    heat of fusion30 kj/mol
    heat of vaporization689.9 kj/mol
    molar heat capacity24.60 j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 2942 3207 3524 3910 4393 5013
    atomic properties
    oxidation states−3, −1, +1, +2, +3, +4, +5 (a mildly acidic oxide)
    electronegativitypauling scale: 1.6
    ionization energies
    • 1st: 652.1 kj/mol
    • 2nd: 1380 kj/mol
    • 3rd: 2416 kj/mol
    atomic radiusempirical: 146 pm
    covalent radius164±6 pm
    color lines in a spectral range
    spectral lines of niobium
    other properties
    natural occurrenceprimordial
    crystal structurebody-centered cubic (bcc)
    cubic body-centered crystal structure for niobium
    speed of sound thin rod3480 m/s (at 20 °c)
    thermal expansion7.3 µm/(m·k)
    thermal conductivity53.7 w/(m·k)
    electrical resistivity152 nΩ·m (at 0 °c)
    magnetic orderingparamagnetic
    young's modulus105 gpa
    shear modulus38 gpa
    bulk modulus170 gpa
    poisson ratio0.40
    mohs hardness6.0
    vickers hardness870–1320 mpa
    brinell hardness735–2450 mpa
    cas number7440-03-1
    history
    namingafter niobe in greek mythology, daughter of tantalus (tantalum)
    discoverycharles hatchett (1801)
    first isolationchristian wilhelm blomstrand (1864)
    recognized as a distinct element byheinrich rose (1844)
    main isotopes of niobium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    90nb syn 15 h β+ 90zr
    91nb syn 680 y ε 91zr
    91mnb syn 61 d it 91nb
    92nb trace 3.47×107 y ε 92zr
    γ
    92m1nb syn 10 d ε 92zr
    γ
    93nb 100% stable
    93mnb syn 16 y it 93nb
    94nb trace 20.3×103 y β 94mo
    γ
    95nb syn 35 d β 95mo
    γ
    95mnb syn 4 d it 95nb
    96nb syn 24 h β 96mo
    category category: niobium
    | references

    niobium, also known as columbium, is a chemical element with the symbol nb (formerly cb) and atomic number 41. niobium is a light grey, crystalline, and ductile transition metal. pure niobium has a hardness similar to that of pure titanium,[2][contradictory] and it has similar ductility to iron. niobium oxidizes in the earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". its name comes from greek mythology, specifically niobe, who was the daughter of tantalus, the namesake of tantalum. the name reflects the great similarity between the two elements in their physical and chemical properties, making them difficult to distinguish.[3]

    the english chemist charles hatchett reported a new element similar to tantalum in 1801 and named it columbium. in 1809, the english chemist william hyde wollaston wrongly concluded that tantalum and columbium were identical. the german chemist heinrich rose determined in 1846 that tantalum ores contain a second element, which he named niobium. in 1864 and 1865, a series of scientific findings clarified that niobium and columbium were the same element (as distinguished from tantalum), and for a century both names were used interchangeably. niobium was officially adopted as the name of the element in 1949, but the name columbium remains in current use in metallurgy in the united states.

    it was not until the early 20th century that niobium was first used commercially. brazil is the leading producer of niobium and ferroniobium, an alloy of 60–70% niobium with iron. niobium is used mostly in alloys, the largest part in special steel such as that used in gas pipelines. although these alloys contain a maximum of 0.1%, the small percentage of niobium enhances the strength of the steel. the temperature stability of niobium-containing superalloys is important for its use in jet and rocket engines.

    niobium is used in various superconducting materials. these superconducting alloys, also containing titanium and tin, are widely used in the superconducting magnets of mri scanners. other applications of niobium include welding, nuclear industries, electronics, optics, numismatics, and jewelry. in the last two applications, the low toxicity and iridescence produced by anodization are highly desired properties. niobium is considered a technology-critical element.

  • history
  • characteristics
  • production
  • compounds
  • applications
  • precautions
  • references
  • external links

Niobium, 41Nb
A lump of gray shining crystals with hexagonal facetting
Niobium
Pronunciationm/ (OH-bee-əm)
Appearancegray metallic, bluish when oxidized
Standard atomic weight Ar, std(Nb)92.90637(1)[1]
Niobium 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
V

Nb

Ta
zirconiumniobiummolybdenum
Atomic number (Z)41
Groupgroup 5
Periodperiod 5
Blockd-block
Element category  Transition metal
Electron configuration[Kr] 4d4 5s1
Electrons per shell2, 8, 18, 12, 1
Physical properties
Phase at STPsolid
Melting point2750 K ​(2477 °C, ​4491 °F)
Boiling point5017 K ​(4744 °C, ​8571 °F)
Density (near r.t.)8.57 g/cm3
Heat of fusion30 kJ/mol
Heat of vaporization689.9 kJ/mol
Molar heat capacity24.60 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2942 3207 3524 3910 4393 5013
Atomic properties
Oxidation states−3, −1, +1, +2, +3, +4, +5 (a mildly acidic oxide)
ElectronegativityPauling scale: 1.6
Ionization energies
  • 1st: 652.1 kJ/mol
  • 2nd: 1380 kJ/mol
  • 3rd: 2416 kJ/mol
Atomic radiusempirical: 146 pm
Covalent radius164±6 pm
Color lines in a spectral range
Spectral lines of niobium
Other properties
Natural occurrenceprimordial
Crystal structurebody-centered cubic (bcc)
Cubic body-centered crystal structure for niobium
Speed of sound thin rod3480 m/s (at 20 °C)
Thermal expansion7.3 µm/(m·K)
Thermal conductivity53.7 W/(m·K)
Electrical resistivity152 nΩ·m (at 0 °C)
Magnetic orderingparamagnetic
Young's modulus105 GPa
Shear modulus38 GPa
Bulk modulus170 GPa
Poisson ratio0.40
Mohs hardness6.0
Vickers hardness870–1320 MPa
Brinell hardness735–2450 MPa
CAS Number7440-03-1
History
Namingafter Niobe in Greek mythology, daughter of Tantalus (tantalum)
DiscoveryCharles Hatchett (1801)
First isolationChristian Wilhelm Blomstrand (1864)
Recognized as a distinct element byHeinrich Rose (1844)
Main isotopes of niobium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
90Nb syn 15 h β+ 90Zr
91Nb syn 680 y ε 91Zr
91mNb syn 61 d IT 91Nb
92Nb trace 3.47×107 y ε 92Zr
γ
92m1Nb syn 10 d ε 92Zr
γ
93Nb 100% stable
93mNb syn 16 y IT 93Nb
94Nb trace 20.3×103 y β 94Mo
γ
95Nb syn 35 d β 95Mo
γ
95mNb syn 4 d IT 95Nb
96Nb syn 24 h β 96Mo
Category Category: Niobium
| references

Niobium, also known as columbium, is a chemical element with the symbol Nb (formerly Cb) and atomic number 41. Niobium is a light grey, crystalline, and ductile transition metal. Pure niobium has a hardness similar to that of pure titanium,[2][contradictory] and it has similar ductility to iron. Niobium oxidizes in the earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology, specifically Niobe, who was the daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, making them difficult to distinguish.[3]

The English chemist Charles Hatchett reported a new element similar to tantalum in 1801 and named it columbium. In 1809, the English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. The German chemist Heinrich Rose determined in 1846 that tantalum ores contain a second element, which he named niobium. In 1864 and 1865, a series of scientific findings clarified that niobium and columbium were the same element (as distinguished from tantalum), and for a century both names were used interchangeably. Niobium was officially adopted as the name of the element in 1949, but the name columbium remains in current use in metallurgy in the United States.

It was not until the early 20th century that niobium was first used commercially. Brazil is the leading producer of niobium and ferroniobium, an alloy of 60–70% niobium with iron. Niobium is used mostly in alloys, the largest part in special steel such as that used in gas pipelines. Although these alloys contain a maximum of 0.1%, the small percentage of niobium enhances the strength of the steel. The temperature stability of niobium-containing superalloys is important for its use in jet and rocket engines.

Niobium is used in various superconducting materials. These superconducting alloys, also containing titanium and tin, are widely used in the superconducting magnets of MRI scanners. Other applications of niobium include welding, nuclear industries, electronics, optics, numismatics, and jewelry. In the last two applications, the low toxicity and iridescence produced by anodization are highly desired properties. Niobium is considered a technology-critical element.