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Name: Promethium
Symbol: Pm
Number of Energy Levels: 6
Electrons on the outer energy level: 2
Atomic number: 61
Atomic Mass: 145 Amu (Atomic Mass Units)
Protons/Electrons: 61
Neutrons: 84
Density: 6.475 g/cm3
Classification: Rare Earth

Promethium | Chemical elements

Promethium was discovered in 1945 by J.A. Marinsky. Its name derives from the name of the god "Prometheus", who has stolen fire from the sky and gave it to man. Promethium’s melting point is at 1315 K (1024 0C, 1908 0F) and its boiling point is at 3273 K (3000 0C, 5432 0F).

Top 11 interesting facts about Promethium

  1. Promethium has similar properties with lanthanides and the neighboring elements neodymium and samarium.
  2. Promethium has the third largest atomic radius among lanthanides.
  3. Promethium is a very instable chemical element therefore its studies are incomplete.
  4. Promethium compounds tend to be pink or reddish in color.
  5. Promethium has no stable isotopes and it forms only one stable oxidation state (+3).
  6. Promethium can be found in nature as a product of uranium-238 fission.
  7. Promethium has been identified in the spectrum of a few stars.
  8. Promethium is industrially produced from uranium-235, uranium-238 or neodymium-147.
  9. Currently, only Russia produces promethium.
  10. Promethium-147 is used in luminous paint, atomic batteries, and to measure the thickness of materials.
  11. Promethium has no known biological role.

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