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Name: Francium
Symbol: Fr
Number of Energy Levels: 7
Electrons on the outer energy level: 1
Atomic number: 87
Atomic Mass: 223.0 Amu (Atomic Mass Units)
Protons/Electrons: 87
Neutrons: 136
Density: Unknown g/cm3
Classification: Alkali Metal

Francium | Chemical elements

Francium was discovered in 1939 by Marguerite Perey. Its name derives from the name of the country France. Francium’s melting point is at 27.0 °C (300.15 K, 80.6 °F) and its boiling point is at 677.0 °C (950.15 K, 1250.6 °F).

Top 14 interesting facts about Francium

  1. Francium was formerly known as eka-caesium and actinium K.
  2. Francium and cesium are the least electronegative elements.
  3. Francium’s chemical properties are similar to those of cesium.
  4. Francium is highly radioactive metal.
  5. Francium decays into astatine, radium, and radon.
  6. Francium has the highest equivalent weight of any element.
  7. Francium is believed to have a highly reflective appearance if it could be viewed in bulk (the intense heat of the decay instantly vaporize any bulk quantity).
  8. Francium is the last element discovered in nature and not by synthesis.
  9. Francium forms and decays in uranium and thorium ores.
  10. Just 20-30g of Francium exists at any given moment on Earth’s crust.
  11. Francium is the most unstable element among those occurring naturally.
  12. Francium does not have commercial applications other than for research purposes.
  13. Francium has 34 known isotopes; none of them stable.
  14. Francium is harmful to human body and has no biological role.

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