Niobium

41
Nb
Gruppe
5
Periode
5
Blok
d
Protons
Electrons
Neutrons
41
41
52
General Properties
Atomnummer
41
Atommasse
92,90638
Mass Number
93
Kategori
Overgangsmetaller
Farve
Grå
Radioactive
Nej
Named after Niobe, the daughter of Tantalu
Krystalstruktur
Rumcentreret Kubisk
History
Niobium was discovered by the English chemist Charles Hatchett in 1801 and named the new element columbium.

In 1846, German chemist Henrich Rose independently discovered the element and named it niobium.

The metal was first isolated by Swedish scientist Christian Wilhelm Blomstrand in 1864 who reduced the chloride by heating it in a hydrogen atmosphere.
Elektroner i hver skal
2, 8, 18, 12, 1
Elektronkonfiguration
[Kr] 4d4 5s1
Nb
Brazil is the leading producer of niobium
Physical Properties
Tilstandsform
Fast stof
Massefylde
8,57 g/cm3
Smeltepunkt
2750,15 K | 2477 °C | 4490,6 °F
Kogepunkt
5017,15 K | 4744 °C | 8571,2 °F
Smeltevarme
26,8 kJ/mol
Fordampningsvarme
690 kJ/mol
Varmefylde
0,265 J/g·K
Abundance in Earth's crust
0,0017%
Abundance in Universe
2×10-7%
Ultrapure
Billede akkrediteringer: Images-of-elements
Ultrapure niobium bead, slightly oxidized
CAS Number
7440-03-1
PubChem CID Number
23936
Atomic Properties
Atomradius
146 pm
Kovalent radius
164 pm
Elektronegativitet
1,6 (Paulings skala)
Ionization Potential
6,7589 eV
Atomic Volume
10,87 cm3/mol
Varmeledningsevne
0,537 W/cm·K
Oxidationstrin
-1, 2, 3, 4, 5
Applications
Niobium is used in arc-welding rods for stabilized grades of stainless steel.

Niobium alloys are strong and are often used in pipeline construction.

The metal is used in superalloys for jet engines and heat resistant equipment.

Niobium is found in many medical devices such as pacemakers.
Some niobium compounds are highly toxic
Isotoper
Stable Isotopes
93Nb
Unstable Isotopes
81Nb, 82Nb, 83Nb, 84Nb, 85Nb, 86Nb, 87Nb, 88Nb, 89Nb, 90Nb, 91Nb, 92Nb, 94Nb, 95Nb, 96Nb, 97Nb, 98Nb, 99Nb, 100Nb, 101Nb, 102Nb, 103Nb, 104Nb, 105Nb, 106Nb, 107Nb, 108Nb, 109Nb, 110Nb, 111Nb, 112Nb, 113Nb