- Atomic Radius (Å)
Niobium, 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.
41
Atomic Number
92.91
Atomic Mass (u)
2741.15
Melting Point (K)
5017
Boiling Point (K)
8.57
Density (solid: g/cm³, gas: g/liter)
2.1
Atomic Radius (Å)
1.64
Covalent Radius (Å)
1.6
Electronegativity
6.76
First Ionization Energy (eV)
88.52
Electron Affinity
5
Number of Shells
2, 8, 18, 12, 1
Electron Shell Occupations
0.27
Specific Heat (J/g)