Tantalum

73
Ta
Gruppe
5
Periode
6
Blok
d
Protons
Electrons
Neutrons
73
73
108
General Properties
Atomnummer
73
Atommasse
180,94788
Mass Number
181
Kategori
Overgangsmetaller
Farve
Grå
Radioactive
Nej
Named after Tantalos, a Greek mythological character, father of Niobe
Krystalstruktur
Rumcentreret Kubisk
History
Tantalum was discovered in Sweden in 1802 by Anders Ekeberg in the minerals tantalite from Finland and yttrotantalite from Sweden.

Unfortunately, William Hyde Wollaston claimed Ekeberg's new element was actually niobium, which had also been discovered in 1802.

In 1846, German chemist Heinrich Rose finally proved beyond doubt that tantalum and niobium were different elements.
Elektroner i hver skal
2, 8, 18, 32, 11, 2
Elektronkonfiguration
[Xe] 4f14 5d3 6s2
Ta
Tantalum occurs principally in the mineral columbite-tantalite
Physical Properties
Tilstandsform
Fast stof
Massefylde
16,654 g/cm3
Smeltepunkt
3290,15 K | 3017 °C | 5462,6 °F
Kogepunkt
5731,15 K | 5458 °C | 9856,4 °F
Smeltevarme
36 kJ/mol
Fordampningsvarme
735 kJ/mol
Varmefylde
0,14 J/g·K
Abundance in Earth's crust
0,00017%
Abundance in Universe
8×10-9%
Tantalum
Billede akkrediteringer: Images-of-elements
Tantalum pieces
CAS Number
7440-25-7
PubChem CID Number
23956
Atomic Properties
Atomradius
146 pm
Kovalent radius
170 pm
Elektronegativitet
1,5 (Paulings skala)
Ionization Potential
7,5496 eV
Atomic Volume
10,90 cm3/mol
Varmeledningsevne
0,575 W/cm·K
Oxidationstrin
-1, 2, 3, 4, 5
Applications
Tantalum is used in the electronics industry for capacitors and high power resistors.

The high melting point and oxidation resistance lead to the use of the metal in the production of vacuum furnace parts.

Tantalum oxide is used to make special glass with high index of refraction for camera lenses.
Tantalum is considered to be non-toxic
Isotoper
Stable Isotopes
181Ta
Unstable Isotopes
155Ta, 156Ta, 157Ta, 158Ta, 159Ta, 160Ta, 161Ta, 162Ta, 163Ta, 164Ta, 165Ta, 166Ta, 167Ta, 168Ta, 169Ta, 170Ta, 171Ta, 172Ta, 173Ta, 174Ta, 175Ta, 176Ta, 177Ta, 178Ta, 179Ta, 180Ta, 182Ta, 183Ta, 184Ta, 185Ta, 186Ta, 187Ta, 188Ta, 189Ta, 190Ta