Niobium |
Symbol | Nb |
---|---|
Latin name | Niobium |
Atomic number | 41 |
Period | 5 |
Element category | Transition elements |
Relative atomic mass | 92.90638 |
Group | V.B |
Electronegativity | 1.6 |
Oxidation numbers | 3, 5 |
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d4 5s1 |
Density [g/cm3] | 8.57 |
State | Solid |
Melting point [°C] | 2468 |
Boiling point [°C] | 4742 |
Atomic radius [pm] | 198 |
Covalent radius [pm] | 137 |
Thermal conductivity [W m-1K-1] | 53.7 |
Heat capacity [J K-1g-1] | 0.265 |
Discovery | 1801 |
Hardness [Mohs scale] | 6.0 |
Vickers hardness [MPa] | 1320 |
Brinell hardness [MPa] | 736 |
Young's modulus [GPa] | 105 |
Electrical conductivity [S m-1] | 6.7 · 106 |
Shear modulus [GPa] | 38 |
1.st ionization energy [eV] | 6.7589 |
2.nd ionization energy [eV] | 14.32 |
3.rd ionization energy [eV] | 25.04 |
Stable isotopes | 1 |
Unstable isotopes | 21 |