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Name: Thorium
Symbol: Th
Number of Energy Levels: 7
Electrons on the outer energy level: 2
Atomic number: 90
Atomic Mass: 232.03 Amu (Atomic Mass Units)
Protons/Electrons: 90
Neutrons: 142
Density: 11.72 g/cm3
Classification: Rare Earth

Thorium | Chemical elements

Thorium was discovered in 1828 by Morten Thrane Esmark but it was identified by Jons Berzelius. Its name derives from the name of the Scandinavian god of thunder, Thor. Thorium’s melting point is at 1750.0 °C (2023.15 K, 3182.0 °F) and its boiling point is at 4790.0 °C (5063.15 K, 8654.0 °F).

Top 15 interesting facts about Thorium

  1. Thorium is a soft, paramagnetic, and radioactive element.
  2. Thorium can be found in nature in usable quantities.
  3. Thorium has a silvery color.
  4. Thorium is a highly reactive metal.
  5. Thorium is soft and ductile.
  6. Thorium oxidizes in the air forming a black layer of oxide.
  7. Thorium is at least three times more abundant than uranium in the Earth’s crust.
  8. Thorium has six naturally occurring isotopes, all of them unstable.
  9. Thorium-232 isotope has a half-life of more than 14 billion years therefore it is considered relatively stable and it makes up almost all natural thorium.
  10. Thorium’s radioactive decay produces an important amount of heat in Earth’s core.
  11. Thorium’s abundance is comparable to that of lead.
  12. Thorium is found and produced mainly from monazite ores.
  13. Thorium is used as a nuclear fuel replacing uranium.
  14. There are about 100 micrograms of thorium in every human body.
  15. A person ingests about three micrograms of thorium every day.

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