Caesium

55
Cs
Gruppe
1
Periode
6
Block
s
Protonen
Elektronen
Neutronen
55
55
78
Generelle Eigenschaften
Ordnungszahl
55
Atommasse
132,9054519
Massenzahl
133
Kategorie
Alkalimetalle
Farbe
Silber
Radioaktiv
Ja
Aus dem Lateinischen caesius (himmelsblau)
Kristallstruktur
Kubisch raumzentriert
Geschichte
Robert Bunsen and Gustav Kirchhoff were the first to suggest finding cesium in 1860 by spectrum analysis.

They discovered cesium by its two blue emission lines in a sample of Dürkheim mineral water.

The pure metal was eventually isolated by the German chemist Carl Setterberg while working on his doctorate with Kekulé and Bunsen.
Elektronen pro Schale
2, 8, 18, 18, 8, 1
Elektronenkonfiguration
[Xe] 6s1
Cs
Cesium was the first element discovered using a spectroscope
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
1,873 g/cm3
Schmelzpunkt
301,59 K | 28,44 °C | 83,19 °F
Siedepunkt
944,15 K | 671 °C | 1239,8 °F
Schmelzwärme
2,09 kJ/mol
Verdampfungswärme
65 kJ/mol
Spezifische Wärmekapazität
0,242 J/g·K
Häufigkeit in der Erdkruste
0,00019%
Häufigkeit im Universum
8×10-8%
Cesium
Danksagungen für Bilder: Wikimedia Commons (Dnn87)
Cesium metal sample from the Dennis s.k collection
CAS-Nummer
7440-46-2
PubChem CID Number
5354618
Atomeigenschaften
Atomradius
265 pm
Kovalenter Radius
244 pm
Elektronegativität
0,79 (Pauling-Skala)
Ionisierungsenergie
3,8939 eV
Molares Volumen
71,07 cm3/mol
Wärmeleitfähigkeit
0,359 W/cm·K
Oxidationszustände
-1, 1
Anwendung
The radioactive isotope cesium-137 has a half-life of about 30 years and is used in medical applications, industrial gauges, and hydrology.

Cesium is also used in photoelectric cells and as a catalyst in the hydrogenation of organic compounds.

Cesium vapor thermionic generators are low-power devices that convert heat energy to electrical energy.
Cesium compounds are considered to be mildly toxic
Isotope
Stabile Isotope
133Cs
Instabile Isotope
112Cs, 113Cs, 114Cs, 115Cs, 116Cs, 117Cs, 118Cs, 119Cs, 120Cs, 121Cs, 122Cs, 123Cs, 124Cs, 125Cs, 126Cs, 127Cs, 128Cs, 129Cs, 130Cs, 131Cs, 132Cs, 134Cs, 135Cs, 136Cs, 137Cs, 138Cs, 139Cs, 140Cs, 141Cs, 142Cs, 143Cs, 144Cs, 145Cs, 146Cs, 147Cs, 148Cs, 149Cs, 150Cs, 151Cs