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41Nb92.906
Niobium
Transition MetalNiobium, formerly columbium, is a chemical element with symbol Nb (formerly Cb) and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite. The name comes from Greek mythology:Niobe, daughter of Tantalus since it is so similar to tantalum.
Phase: SolidAppearance: gray metallic, bluish when oxidized
2, 8, 18, 12, 1
Physical Properties
Atomic Mass92.906372 u
Density8.57 g/cm³
Melting Point2750 K
Boiling Point5017 K
Molar Heat24.6 J/(mol·K)
Period5
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d4
Semantic Config[Kr] 4d4 5s1
Shells2, 8, 18, 12, 1
Electron Affinity88.516 kJ/mol
Electronegativity1.6
Ionization Energies
IE1: 652.1 kJ/molIE2: 1380 kJ/molIE3: 2416 kJ/molIE4: 3700 kJ/molIE5: 4877 kJ/molIE6: 9847 kJ/molIE7: 12100 kJ/mol
Discovery
Discovered byCharles Hatchett