Periodic table / Transition metals

41Niobium

Niobium is a transition metal in group 5, period 5. At 25 °C it is a solid.

Nb
Shells: 2, 8, 18, 12, 1. A simple picture: electrons do not move in circles.
Symbol
Nb
Atomic number
41 protons in the nucleus
Standard atomic weight
92.906 ± 0.001
Electron configuration
[Kr] 4d4 5s1
Electrons in each shell
2, 8, 18, 12, 1
Group, period, block
5, 5, d
Family
Transition metals
State at 25 °C
solid
Electronegativity
1.6 (Pauling scale)
First ionisation energy
652.1 kJ/mol (6.75885 eV)
Where these numbers come from

Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.