Periodic Table of Elements

Element Cesium - Cs

Comprehensive data on the chemical element Cesium is provided on this page; including scores of properties, element names in many languages, most known nuclides of Cesium. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

Cesium Menu

Overview of Cesium

Cesium's Name in Other Languages

  • Latin: Caesium
  • Czech: Cesium
  • Croatian: Cezij
  • French: Césium
  • German: Zäsium - s
  • Italian: Cesio
  • Norwegian: Cesium
  • Portuguese: Césio
  • Russian: Цеэий
  • Spanish: Cesio
  • Swedish: Cesium

Atomic Structure of Cesium

Chemical Properties of Cesium

Physical Properties of Cesium

Regulatory / Health

  • CAS Number
    • 7440-46-2
  • RTECS: FK9225000
  • OSHA Permissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSH Recommended Exposure Limit (REL)
    • No limits set by NIOSH
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: 0.0038
    • Bone/p.p.m: 0.013-0.052
    • Liver/p.p.m: 0.04-0.05
    • Muscle/p.p.m: 0.07-1.6
    • Daily Dietary Intake: 0.004-0.03 mg
    • Total Mass In Avg. 70kg human: 6 mg

Who / Where / When / How

  • Discoverer: Gustov R. Kirchoff, Robert Bunsen
  • Discovery Location: Heidelberg Germany
  • Discovery Year: 1860
  • Name Origin:
    Latin: caesius (sky blue); its salts turn flames blue.
  • Abundance of Cesium:
    • Earth's Crust/p.p.m.: 3
    • Seawater/p.p.m.: 0.0003
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 80
  • Sources of Cesium:
    Found in pollucite [(Cs4Al4Si9O26).H2O] and as trace in lepidolite. World production is around 20 tons per year. Primary mining areas are in Bernic Lake (Manitoba, Canada), Bikita (Zimbabwe) and South-West Africa.
  • Uses of Cesium:
    Used as a 'getter' to remove air traces in vacuum tubes. Since it ionizes readily, it is used as an ion rocket motor propellant. Also used in photoelectric cells, atomic clocks, infared lamps.
  • Additional Notes:
    Cesium can have very serious effects on the body if taken in excess.

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A list of reference sources used to compile the data provided on our periodic table of elements can be found on the main periodic table page.

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