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Niobium [Nb]
CAS-ID: 7440-03-1
An: 41 N: 52
Am: 92.90638 g/mol
Group No: 5
Group Name: Transition metals
Block: d-block  Period: 5
State: solid at 298 K
Colour: grey metallic Classification: Metallic
Boiling Point: 5017K (4744°C)
Melting Point: 2750K (2477°C)
Superconducting temperature: 9.25K (-263.9°C)
Density: 8.57g/cm3
Discovery Information
Who: Charles Hatchet
When: 1801
Where: England
Name Origin
From Niobe; daughter of the mythical Greek king Tantalus.
 "Niobium" in different languages.
Sources
Occurs in the minerals columbite ([(Fe, Mn)(Nb, Ta)2O6]), columbite-tantalite, pyrochlore ((Na,Ca)2Nb2O6(OH,F)) and euxenite ((Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6). Brazil and Canada are the major producers of niobium mineral concentrates and extensive ore reserves are also in Nigeria, Democratic Republic of Congo, and in Russia.
Around 15 thousand tons are produced annually.
Abundance
 Universe: 0.002 ppm (by weight)
 Sun: 0.004 ppm (by weight)
 Carbonaceous meteorite: 0.19 ppm
 Earth's Crust: 17 ppm
 Seawater: 9 x 10-7 ppm
Uses
It is used in stainless steel alloys for nuclear reactors, jets, missiles, cutting tools, pipelines, super magnets and welding rods. Because of its bluish colour, niobium is also used in body piercing jewellery (usually as an alloy).
Appreciable amounts of niobium in the form of high-purity ferroniobium and nickel niobium are used in nickel-, cobalt-, and iron-base superalloys for such applications as jet engine components, rocket subassemblies, and heat-resisting and combustion equipment. For example, advanced air frame systems such as those used in the Gemini program used this metal.
Niobium is also added to glass in order to attain a higher refractive index, a property used in the optical industry to make thinner corrective glasses.
History
Niobium (Greek mythology: Niobe, daughter of Tantalus) was discovered by Charles Hatchett in 1801. Hatchett found niobium in columbite ore that was sent to England in the 1750s by John Winthrop, the first governor of Connecticut. There was a considerable amount of confusion about the difference between the closely-related niobium and tantalum that wasn't resolved until 1846 by Heinrich Rose and Jean Charles Galissard de Marignac, who rediscovered the element. Since Rose was unaware of Hatchett's work, he gave the element a different name, niobium. In 1864 Christian Blomstrand was the first to prepare the pure metal, reducing niobium chloride by heating it in a hydrogen atmosphere.
Columbium (symbol Cb) was the name originally given to this element by Hatchett, but the International Union of Pure and Applied Chemistry (IUPAC) officially adopted "niobium" as the name for element 41 in 1950 after 100 years of controversy. This was a compromise of sorts; the IUPAC accepted tungsten instead of wolfram, in deference to North American usage; and niobium instead of columbium, in deference to European usage. Not everyone agreed, however, and while many leading chemical societies and government organizations refer to it by the official IUPAC name, many leading metallurgists, metal societies, and most leading American commercial producers still refer to the metal by the original "columbium."
Notes
Previously known as Columbium (Cb).
Hazards
Niobium containing compounds are relatively rarely encountered by most people but many are highly toxic and should be treated with care. Metallic niobium dust is an eye and skin irritant and also can be a fire hazard.
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