Niobium

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Niobium,  41Nb
A lump o gray shinin creestals wi hexagonal facettin
General properties
Appearance gray metallic, bluish whan oxidised
Staundart atomic wecht (Ar, staundart) 92.90637(2)
Niobium in the periodic cairt
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 Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) 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 Gowd Mercur (element) Thallium Leid (element) 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 Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium
V

Nb

Ta
zirconiumniobiummolybdenum
Atomic nummer (Z) 41
Group group 5
Period period 5
Block d-block
Electron confeeguration [Kr] 4d4 5s1
Electrons per shell
2, 8, 18, 12, 1
Pheesical properties
Phase (at STP) solit
Meltin pynt 2750 K ​(2477 °C, ​4491 °F)
Bylin pynt 5017 K ​(4744 °C, ​8571 °F)
Density (near r.t.) 8.57 g/cm3
Heat o fusion 30 kJ/mol
Heat o vapourisation 689.9 kJ/mol
Molar heat capacity 24.60 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2942 3207 3524 3910 4393 5013
Atomic properties
Oxidation states 5, 4, 3, 2, -1
(mildly acidic oxide)
Electronegativity Pauling scale: 1.6
Atomic radius empirical: 146 pm
Covalent radius 164±6 pm
Color lines in a spectral range
Miscellanea
Creestal structurbody-centred cubic (bcc)
Cubic body-centered creestal structur for niobium
Speed o soond thin rod 3480 m/s (at 20 °C)
Thermal expansion 7.3 µm/(m·K)
Thermal conductivity 53.7 W/(m·K)
Electrical resistivity 152 n Ω·m (at 0 °C)
Magnetic orderin paramagnetic
Young's modulus 105 GPa
Shear modulus 38 GPa
Bouk modulus 170 GPa
Poisson ratio 0.40
Mohs haurdness 6.0
Vickers haurdness 1320 MPa
Brinell haurdness 736 MPa
CAS Nummer 7440-03-1
History
Diskivery Charles Hatchett (1801)
First isolation Christian Wilhelm Blomstrand (1864)
Recognised as a distinct element by Heinrich Rose (1844)
Main isotopes o niobium
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
91Nb syn 6.8×102 y ε 91Zr
91mNb syn 60.86 d IT 91Nb
92Nb syn 10.15 d ε 92Zr
γ -
92Nb syn 3.47×107y ε 92Zr
γ -
93Nb 100% - (SF)
93mNb syn 16.13 y IT 93Nb
94Nb syn 2.03×104 y β 94Mo
γ -
95Nb syn 34.991 d β 95Mo
γ -
95mNb syn 3.61 d IT 95Nb
Decay modes in parentheses are predicted, but hinna been observed yet
| references | in Wikidata

Niobium, umwhile columbium, is a chemical element wi the seembol Nb (umwhile Cb) an atomic nummer 41. It is a saft, grey, ductile transeetion metal, whilk is aften foond in the pyrochlore mineral, the main commercial soorce for niobium, an columbite. The name comes frae Greek meethology: Niobe, dauchter o Tantalus.