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41 · Nb

Niobium

Described as columbium by Hatchett in 1801 and long confused with tantalum. Marignac separates them in 1864.

Identity

Atomic number
41
Symbol
Nb
Canonical name
Niobium
Category
transition metal
Group
5
Period
5
Block
d
Former names
columbium

Properties

These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.

Atomic mass
92.906372 u
Electron configuration
[Kr] 4d4 5s1
Electrons per shell
2, 8, 18, 12, 1
Standard state
solid
Density
8.57 g/cm³
Melting point
2,750 K
Boiling point
5,017 K
Electronegativity
1.6 Pauling
First ionization energy
652.1 kJ/mol
Electron affinity
88.516 kJ/mol

Notable isotopes

This summary is not an inventory of every isotope.

  • Nb-93 · 100 % · stable

History

Columbium

Discovery · disputed · 1801

Hatchett describes columbium in an American ore. Confusion with tantalum lasts for decades.

The name niobium

Naming · claimed · 1844

Rose believes he has distinguished an element and names it niobium. A clean separation comes later.

Separation from tantalum

Identification · confirmed · 1864

Marignac demonstrates that niobium and tantalum are two elements.

See the element timeline

Etymology

Theme
mythology
Language
grec
Root
Niobe
Meaning
Niobe

History of the symbol

  • Cb · former — Symbol of columbium, long used in parallel in Anglo-American usage.
  • Nb · definitive — Symbol kept with the name niobium.

Scientists

Places and institutions

  • London — historical setting : United Kingdom — present country : United Kingdom
  • Berlin — historical setting : Prussia, then Germany — present country : Germany

See also

Sources