Chemical data for Cs - Cesium | PhysLink.com

Cesium

 Cesium 
Cs
Atomic Number: 55
Atomic Weight: 132.90543
Element Type: Alkali Metal
Crystal Structure: Cubic Face Centered
Melting Point: 28.44°C = 83.192°F = 301.59 K
Boiling Point: 671.0°C = 1239.8°F = 944.15 K
Critical Temp: °C = °F = K
Atomic Radius: 3.34 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 2.35 Å
Electronegativity: 0.79

History

(L. caesius, sky blue) Cesium was discovered spectroscopically by Bunsen and Kirchhoffin 1860 in mineral water from Durkheim.


Sources

Cesium, an alkali metal, occurs in lepidolite, pollucte (a hydrated silicate ofaluminum and cesium), and in other sources. One of the world's richest sources of cesiumis located at Bernic Lake, Manitoba. The deposits are estimated to contain 300,000 tons ofpollucite, averaging 20% cesium.

It can be isolated by elecytrolysis of the fused cyanide and by a number of othermethods. Very pure, gas-free cesium can be prepared by thermal decomposition of cesiumazide.