| Ordnungszahl: |
27 |
| Name: |
Cobalt |
| Namensursprung: |
German: kobold (goblin). |
| Entdeckung: |
1739 by George Brandt in Sweden |
| Beschreibung: |
Hard, ductile, lustrous bluish-gray metal. Exists in the earth's curst in cocentrations of about 25 ppm. It has remarkable magnetic properties. |
| Vorkommen: |
Occurs in compounds with arsenic, oxygen and sulfur as in cobaltine (CoAsS) and linneite (Co3S4). Pure cobalt is obtained as a byproduct of refining nickel, copper and iron. |
| Verwendung: |
Used in many hard alloys; for magnets, ceramics and special glasses. Remains hard up to 982°C. Radioactive cobalt-60 is used in cancer therapy. |
| Gruppe: |
Transition Metal |
| Atomgewicht: |
58.93320 |
| Schmelzpunkt: |
1495°C |
| Siedepunkt: |
2927°C |
| Dichte bei 293 K: |
8.90 g/cm³ |
| Aggregatszustand bei Raumtemperatur: |
Solid |
| Schalen: |
2,8,15,2 |
| Orbitale: |
[Ar] 3d7 4s2 |
| Valenzen: |
2,3 |
| 1. Ionisierungs- potential: |
7.8810 V |
| 2. Ionisierungs- potential: |
17.06 V |
| 3. Ionisierungs- potential: |
33.50 V |
| Atomradius: |
1.67 Å |
| Spezifische Wärme: |
0.42 J/gK |
| Verdampfungswärme: |
376.50 kJ/mol |
| Schmelzwärme: |
16.190 kJ/mol |
| Thermischer Ausdehnungskoeffizient: |
13 10-6 K-1 |
| Röntgenemission Energie / Wellenlänge: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| eV |
6925.55 |
7649.69 |
776.267 |
791.43 |
0 |
0 |
|
|
|
| Å |
1.79026 |
1.62079 |
15.972 |
15.666 |
0 |
0 |
|
|
|
|
| Röntgenabsorption Energie / Wellenlänge: |
| |
K |
L-I |
L-II |
L-III |
M-I |
M-II |
M-III |
M-IV |
M-V |
| eV |
7709 |
0 |
793.8 |
779 |
0 |
61 |
0 |
0 |
0 |
| Å |
1.60832 |
0 |
15.6192 |
15.916 |
0 |
203.255 |
0 |
0 |
0 |
|
| Röntgen Fluoreszenz Ausbeute: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| |
38.1% |
0% |
0.4% |
0% |
0% |
0% |
|
|
|
|
| Nuklide: |
| |
Anteil |
Gewicht |
Spin |
Halbwertszeit |
Zerfallsmodus |
| Co56 |
0% |
55.94 |
4 |
77.3d |
EC,β+ |
| Co57 |
0% |
56.936 |
7/2 |
271.8d |
EC |
| Co58 |
0% |
57.936 |
2 |
70.88d |
EC,β+ |
| Co58m |
0% |
58 |
5 |
9.1h |
IT |
| Co59 |
100% |
58.9332 |
7/2 |
|
Stable |
| Co60 |
0% |
59.934 |
5 |
5.271y |
β- |
| Co60m |
0% |
60 |
2 |
10.47m |
IT,β- |
| Co61 |
0% |
61 |
7/2 |
1.65h |
β- |
|
