ElementsWhat is niobium?
Niobium is a soft, grey metal. It becomes a superconductor at low temperatures.
What is niobium used for?
Strong steels for pipelines and car bodies, and superconducting magnets for MRI scanners and particle accelerators.
Where the name comes from
From Niobe of Greek myth, the daughter of Tantalus. Niobium is always found with tantalum.
Key facts
- Symbol
- Nb
- Atomic number
- 41
- Atomic mass
- 92.90637 u
- Family
- Transition metal
- Period
- 5
- Group
- 5
- Block
- d
- State at room temperature
- Solid
- Melting point
- 2,477 °C (2,750 K, 4,490 °F)
- Boiling point
- 4,744 °C (5,017 K, 8,571 °F)
- Density
- 8.57 g/cm³
- Electrons per shell
- 2, 8, 18, 12, 1
- Electron configuration
- [Kr]5s1 4d4
- Common oxidation states
- +5, +3
- Electronegativity (Pauling)
- 1.6
- First ionisation energy
- 6.759 eV
- Electron affinity
- 0.893 eV
- Atomic radius (van der Waals)
- 207 pm
- Discovered
- 1801
Place in the periodic table
Niobium is element number 41. It sits in period 5 (row 5) of the periodic table, in group 5 (column 5), and belongs to the d-block. Just before it comes zirconium (40), and just after it comes molybdenum (42). In the same column, vanadium is above it and tantalum is below it. Elements in one column tend to behave alike.
Family: Transition metals.
Physical properties
At room temperature niobium is a solid. It melts at 2,477 °C and boils at 4,744 °C, so it stays liquid over a range of 2,267 degrees. Its density is 8.57 grams per cubic centimetre, so a one-litre block would weigh about 8.57 kilograms. By density it ranks 37th among the 96 elements with a measured value. It has the 7th highest melting point of all elements.
Inside the atom
An atom of niobium has 41 protons in its nucleus and, when neutral, 41 electrons around it. The electrons are arranged in 5 shells: 2, 8, 18, 12, 1. The outermost shell holds 1 electron. Written in full, the electron configuration is [Kr]5s1 4d4.
Its electronegativity on the Pauling scale is 1.6. This number shows how strongly an atom pulls shared electrons towards itself: fluorine, the strongest, is 3.98. Removing one electron from an atom takes 6.759 electronvolts (about 652 kilojoules per mole). One mole of niobium weighs 92.90637 grams, so a single gram contains about 6.48 × 1021 atoms.
The ring picture is a simple model that only counts the electrons in each shell. Real atoms do not look like this.
Next steps
- Work out the weight of a compound that contains niobium with the molar mass calculator.
- Compare it with every other element in the sortable list.
- Test yourself with the symbol quiz.
Figures on this page are from PubChem (U.S. National Library of Medicine), as downloaded on 11 November 2026. See About and data sources.