Periodic Table of Elements




Niobium was discovered by the English chemist Charles Hatchett in 1801.

Name: Niobium
Symbol: Nb
Atomic number: 41
Atomic weight: 92.906
State: solid
Group, period, block: 5, 5, d
Color: gray metallic, bluish when oxidized
Classification: transition metal
Electron configuration: 4d4 5s1

Physical properties

Density: 8.57 g/cm-3
Melting point: 2750 K,2477 C,4491 F
Boiling point: 5017 K,4744 C,8571 F

Atomic properties

Oxidation states: 5, 4, 3, 2, -1
Electronegativity: 1.86 (Pauling scale)
Ionization energies: 1st: 652.1 kJmol-1
Covalent radius: 1646 pm
Van der Waals radius: no data
  • Nb
  • Electron Configuration


There is one naturally occurring isotope of niobium exists, 93Nb.