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Name: Rubidium
Symbol: Rb
Number of Energy Levels: 5
Electrons on the outer energy level: 1
Atomic number: 37
Atomic Mass: 85.4678 Amu (Atomic Mass Units)
Protons/Electrons: 37
Neutrons: 48
Density: 1.532 g/cm3
Classification: Alkali Metal

Rubidium | Chemical elements

Rubidium was discovered in 1861 by the German chemists Robert Bunsen and Gustav Kirchhoff. Its name derives from the Latin word "rubidius" which means "red". Rubidium’s boiling point is at 688.0 °C (961.15 K, 1270.4 °F) and its melting point is at 38.89 °C (312.04 K, 102.002 °F).

Top 11 interesting facts about rubidium

  1. Rubidium’s color is metallic silver-white.
  2. Elemental rubidium is soft, ductile, and very reactive.
  3. Rubidium’s reaction with water is very violent and can causes fire.
  4. Rubidium has only one stable isotope, 85-Rb.
  5. Rubidium is not a necessary element for living organisms.
  6. Rubidium chloride is the most used rubidium compound.
  7. Rubidium is also used in dating rocks.
  8. Rubidium is the 23rd most abundant element in Earth’s crust (similar to zinc and cooper).
  9. Bernic Lake in Canada and Island of Elba in Italy are two important sources of rubidium.
  10. Just 2 to 4 tones of rubidium are produced annually mainly at the locations mentioned above which are important sources of cesium as well.
  11. Rubidium is kept under a dry mineral oil or sealed in glass ampules in an inert atmosphere.

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