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Nb

Niobium is a chemical element that has the symbol Nb and atomic number 41. A rare, soft, gray, ductile transition metal, niobium is found in pyrochlore and columbite. It was first discovered in the latter mineral and so was initially named columbium; now that mineral is also called "niobite". Niobium is used in special steel alloys as well as in welding, nuclear industries, electronics, optics and jewelry.

Niobium is a shiny gray, ductile metal that takes on a bluish tinge when exposed to air at room temperature for extended periods. Niobium's chemical properties are almost identical to the chemical properties of tantalum, which appears below niobium in the periodic table.

When it is processed at even moderate temperatures niobium must be placed in a protective atmosphere. The metal begins to oxidize in air at 200 ° C; its most common oxidation states are +3, and +5, although others are also known.

TECHNICAL DATA
SymbolNbDensity (20°C)/gcm-38.57
Atomic number41Melting point / °C2468
No. of naturally occurring isotopes1Boiling point / °C4758
Atomic weight92.9064ΔHfus/kJmol-126.8
Electronic configuration[Kr]4d35s2ΔHvap/kJmol-1680.2
Metal radius) 12-coordinate)/pm146ΔHf(monoatomic gas)/kJmol-1724
Ionic radius! 6-coordinate)/pm V64Electrical resistivity (20°C)/μohm cm~12.5
Ionic radius!6-coordinate)/pm IV68Electronegativity χ1.6
Ionic radius! 6-coordinate)/pm III72




Nb
Evaporation Materials
Matierial SymbolAtomic Number     Thermal Conductivity         Theoretical Density 
W/m.Kg/cc
Nb ( pellets )Nb 41548.578



Below is the periodic table of chemical elements.The elements in red are the ones Nexteck's product contain. Click them, you will come to the details.

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