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Cesium at Chemical Elements.com
Basic Information | Atomic Structure | Isotopes | Related Links | Citing This Page

Basic Information

Name: Cesium
Symbol: Cs
Atomic Number: 55
Atomic Mass: 132.90546 amu
Melting Point: 28.5 °C (301.65 K, 83.3 °F)
Boiling Point: 678.4 °C (951.55005 K, 1253.12 °F)
Number of Protons/Electrons: 55
Number of Neutrons: 78
Classification: Alkali Metal
Crystal Structure: Cubic
Density @ 293 K: 1.873 g/cm3
Color: silver
British Spelling: Caesium
IUPAC Spelling: Caesium

Atomic Structure

[Bohr Model of Cesium]  
Number of Energy Levels: 6

    First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 18
    Fifth Energy Level: 8
    Sixth Energy Level: 1


Isotope Half Life
Cs-1261.6 minutes
Cs-1291.3 days
Cs-1319.7 days
Cs-1326.4 days
Cs-1342.1 years
Cs-134m2.9 hours
Cs-1352300000.0 years
Cs-13613.2 days
Cs-13730.2 years
Cs-13832.2 minutes
Cs-1399.3 minutes


Date of Discovery: 1860
Discoverer: Fustov Kirchoff
Name Origin: From the Latin word caesius (sky blue)
Uses: removes air traces in vacuum tubes
Obtained From: pollucite, lepidolite

Related Links

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  1. Cesium Links
    • An index of cesium-related web pages on the Internet
If you know of any other links for Cesium, please let me know

MLA Format for Citing This Page

Bentor, Yinon. Chemical Element.com - Cesium. <http://www.chemicalelements.com/elements/cs.html>.

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