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| Atomic Number: | 41 | Atomic Symbol: | Nb | | Atomic Weight: | 92.9064 | Electron Configuration: | 2-8-18-12-1 | | Shells: | 2,8,18,12,1 | Filling Orbital: | 4d4 | | Melting Point: | 2468oC | Boiling Point: | 4927oC | | Uses: | For welding rods. |
History(Niobe, daughter of Tantalus) Discovered in 1801 by Charles
Hatchet in an ore sent to England more than a century before by John Winthrop
the Younger, first governor of Connecticut.
SourcesThe metal was first prepared in 1864 by Blomstrand, who reduced
the chloride by heating it in a hydrogen atmosphere. The name niobium was
adopted by the International Union of Pure and Applied Chemistry in 1950 after
100 years of controversy. Many leading chemical societies and government
organizations refer to it by this name. Most metallurgists, leading metal
societies, and all but one of the leading U.S. commercial producers, however,
still refer to the metal as "columbium." The element is found in niobite (or
columbite), niobite-tantalite, parochlore, and euxenite. Large deposits of
niobum have been found associated with carbonatites (carbon-silicate rocks), as
a constituent of parochlore. Extensive ore reserves are found in Canada, Brazil,
Nigeria, Zaire, and in Russia. The metal can be isolated from tantalum, and
prepared in several ways.
Properties- It is a shiny, white, soft, and ductile metal, and takes on a bluish cast
when exposed to air at room temperatures for a long time.
- The metal starts to oxidize in air at 200C, and when processed at even
moderate temperatures must be placed in a protective atmosphere. It is used in
arc-welding rods for stabilized grades of stainless steel.
Uses- Thousands of pounds of niobium have beeen used in advanced air frame systems
such as were used in the Gemini space program.
- The element has superconductive properties; superconductive magnets have
been made with Nb-Zr wire, which retains its superconductivity in strong
magnetic fields.
- This type of application offers hope of direct large-scale generation of
electric power.
IsotopesEighteen isotopes of niobium are known.
CostNiobium metal (99.5% pure) is priced at about $75/lb.
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