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Name: Cesium
Symbol: Cs
Number of Energy Levels: 6
Electrons on the outer energy level: 1
Atomic number: 55
Atomic Mass: 132.9054 Amu (Atomic Mass Units)
Protons/Electrons: 55
Neutrons: 78
Density: 1.873 g/cm3
Classification: Alkali Metal

Cesium | Chemical elements

Cesium (Caesium) was discovered in 1860 by Fustov Kirchoff. Its name derives from the Latin word "caesius" which means "blue sky". Cesium’s melting point is at 28.5 °C (301.65 K, 83.3 °F) and its boiling point is at 678.4 °C (951.55005 K, 1253.12 °F).

Top 14 interesting facts about Cesium

  1. Cesium is a soft silvery-gold metal.
  2. Cesium has the lowest hardness of all elements.
  3. Cesium is liquid at room temperature.
  4. Cesium is very reactive.
  5. Cesium can form alloy with gold.
  6. Cesium reacts with water under all conditions.
  7. Cesium ignites in presents of air.
  8. Cesium is the most electropositive stable chemical element.
  9. Cesium is used in atomic clocks.
  10. Cesium has 39 known isotopes.
  11. Cesium has only one stable isotope 133-Cs which has 78 neutrons.
  12. Cesium is the 45th most abundant element on Earth (36th most abundant metal).
  13. Cesium is obtained mainly from pollucite ore.
  14. The largest deposits of cesium are located in Canada (Bernic Lake, Manitoba).

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