Cæsium

55
Cs
Gruppe
1
Periode
6
Blok
s
Protoner
Elektroner
Neutroner
55
55
78
Generelle Egenskaber
Atomnummer
55
Atommasse
132,9054519
Masseantal
133
Kategori
Alkalimetaller
Farve
Sølv
Radioaktiv
Ja
From the Latin word caesius, sky blue
Krystalstruktur
Rumcentreret Kubisk
Historie
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.
Elektroner i hver skal
2, 8, 18, 18, 8, 1
Elektronkonfiguration
[Xe] 6s1
Cs
Cesium was the first element discovered using a spectroscope
Fysiske Egenskaber
Tilstandsform
Fast stof
Massefylde
1,873 g/cm3
Smeltepunkt
301,59 K | 28,44 °C | 83,19 °F
Kogepunkt
944,15 K | 671 °C | 1239,8 °F
Smeltevarme
2,09 kJ/mol
Fordampningsvarme
65 kJ/mol
Varmefylde
0,242 J/g·K
Forekomst i jordskorpen
0,00019%
Forekomst i universet
8×10-8%
Cesium
Billede akkrediteringer: Wikimedia Commons (Dnn87)
Cesium metal sample from the Dennis s.k collection
CAS-nummer
7440-46-2
PubChem CID-nummer
5354618
Atomare egenskaber
Atomradius
265 pm
Kovalent radius
244 pm
Elektronegativitet
0,79 (Paulings skala)
Ioniseringspotentiale
3,8939 eV
Atomvolumen
71,07 cm3/mol
Varmeledningsevne
0,359 W/cm·K
Oxidationstrin
-1, 1
Anvendelser
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
Isotoper
Stabile isotoper
133Cs
Ustabile isotoper
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