| Ordnungszahl: |
73 |
| Name: |
Tantalum |
| Namensursprung: |
From king Tantalus of Greek mythology, father of Niobe. |
| Entdeckung: |
1802 by Anders Ekeberg in Sweden |
| Beschreibung: |
Rare, gray, heavy, hard but ductile, metal with a high melting point. |
| Vorkommen: |
Chiefly occurs in the mineral tantalite. Always found with niobium. |
| Verwendung: |
Often used as an economical substitute for platinum. Tantalum pentoxide is used in capacitors and in camera lenses to increase refracting power. It and its alloys are corrosion and wear resistant so it is used to make surgical and dental tools. |
| Gruppe: |
Transition Metal |
| Atomgewicht: |
180.9479 |
| Schmelzpunkt: |
2996°C |
| Siedepunkt: |
5425°C +/-100°C |
| Dichte bei 293 K: |
16.6 g/cm³ |
| Aggregatszustand bei Raumtemperatur: |
Solid |
| Schalen: |
2,8,18,32,11,2 |
| Orbitale: |
[Xe] 4f14 5d3 6s2 |
| Valenzen: |
3,5 |
| 1. Ionisierungs- potential: |
7.89 V |
| 2. Ionisierungs- potential: |
-- |
| 3. Ionisierungs- potential: |
-- |
| Atomradius: |
2.09 Å |
| Spezifische Wärme: |
0.14 J/gK |
| Verdampfungswärme: |
743.0 kJ/mol |
| Schmelzwärme: |
31.60 kJ/mol |
| Thermischer Ausdehnungskoeffizient: |
6.3 10-6 K-1 |
| Röntgenemission Energie / Wellenlänge: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| eV |
0 |
0 |
8146.38 |
9343.43 |
1709.67 |
1765.42 |
|
|
|
| Å |
0 |
0 |
1.52197 |
1.32698 |
7.25201 |
7.023 |
|
|
|
|
| Röntgenabsorption Energie / Wellenlänge: |
| |
K |
L-I |
L-II |
L-III |
M-I |
M-II |
M-III |
M-IV |
M-V |
| eV |
67412 |
11681 |
11135 |
9881 |
2708 |
2469 |
2194 |
1794 |
1735 |
| Å |
0.18392 |
1.06143 |
1.11347 |
1.25479 |
4.57849 |
5.02168 |
5.65111 |
6.91111 |
7.14613 |
|
| Röntgen Fluoreszenz Ausbeute: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| |
95.6% |
0% |
29.4% |
0% |
0% |
0% |
|
|
|
|
| Nuklide: |
| |
Anteil |
Gewicht |
Spin |
Halbwertszeit |
Zerfallsmodus |
| Ta179 |
0% |
179 |
7/2 |
1.8y |
EC |
| Ta180 |
0.012% |
179.948 |
9 |
>1.2E15y |
EC,β+ |
| Ta181 |
99.988% |
180.948 |
7/2 |
|
Stable |
| Ta182 |
0% |
182 |
3 |
114.43d |
β- |
|
