| Ordnungszahl: |
34 |
| Name: |
Selenium |
| Namensursprung: |
Greek: selênê (moon) |
| Entdeckung: |
1818 by Jöns Berzelius in Sweden |
| Beschreibung: |
Soft metalloid similar to sulfur. Ranges from gray metallic to red glassy appearance. |
| Vorkommen: |
Obtained from lead, copper and nickel refining. Conducts electricity when struck by light. |
| Verwendung: |
Light causes it to conduct electricity more easily. It is used in photoelectric cells, TV cameras, xerography machines and as a semiconductor in solar batteries and rectifiers. Also colors glass red. |
| Gruppe: |
Non-Metal |
| Atomgewicht: |
78.96 |
| Schmelzpunkt: |
217°C |
| Siedepunkt: |
684.9°C |
| Dichte bei 293 K: |
4.79 g/cm³ |
| Aggregatszustand bei Raumtemperatur: |
Solid |
| Schalen: |
2,8,18,6 |
| Orbitale: |
[Ar] 3d10 4s2 4p4 |
| Valenzen: |
-2,4,6 |
| 1. Ionisierungs- potential: |
9.7524 V |
| 2. Ionisierungs- potential: |
21.19 V |
| 3. Ionisierungs- potential: |
30.82 V |
| Atomradius: |
1.22 Å |
| Spezifische Wärme: |
0.32 J/gK |
| Verdampfungswärme: |
37.70 kJ/mol |
| Schmelzwärme: |
6.694 kJ/mol |
| Thermischer Ausdehnungskoeffizient: |
45.0 10-6 K-1 |
| Röntgenemission Energie / Wellenlänge: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| eV |
11209 |
12496.3 |
1379.15 |
1419.28 |
0 |
0 |
|
|
|
| Å |
1.10612 |
0.99217 |
|
8.98999 |
8.7358 |
0 |
|
|
|
|
| Röntgenabsorption Energie / Wellenlänge: |
| |
K |
L-I |
L-II |
L-III |
M-I |
M-II |
M-III |
M-IV |
M-V |
| eV |
12658 |
1654 |
1477 |
1436 |
0 |
0 |
0 |
0 |
54.43 |
| Å |
0.97950 |
7.49609 |
8.39441 |
8.63408 |
0 |
0 |
0 |
0 |
227.789 |
|
| Röntgen Fluoreszenz Ausbeute: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| |
59.6% |
0% |
1.4% |
0% |
0% |
0% |
|
|
|
|
| Nuklide: |
| |
Anteil |
Gewicht |
Spin |
Halbwertszeit |
Zerfallsmodus |
| Se73 |
0% |
73 |
0 |
7.15h |
β- |
| Se74 |
0.87% |
73.9225 |
0 |
|
Stable |
| Se75 |
0% |
74.923 |
0 |
119.78d |
β- |
| Se76 |
9.02% |
75.9192 |
0 |
|
Stable |
| Se77 |
7.58% |
76.9199 |
1/2 |
|
Stable |
| Se78 |
23.52% |
77.9173 |
0 |
|
Stable |
| Se79 |
0% |
78.919 |
7/2 |
~6.5E04y |
β- |
| Se80 |
49.82% |
79.9165 |
0 |
|
Stable |
| Se82 |
9.19% |
81.9167 |
0 |
|
Stable |
|
