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Name: Astatine
Symbol: At
Number of Energy Levels: 6
Electrons on the outer energy level: 7
Atomic number: 85
Atomic Mass: 210.0 Amu (Atomic Mass Units)
Protons/Electrons: 85
Neutrons: 125
Density: Unknown
Classification: Halogen

Astatine | Chemical elements

Astatine was discovered in 1940 by D.R. Corson. Its name derives from the Greek word "astatos" which means "unstable". Astatine’s melting point is at 302.0 °C (575.15 K, 575.6 °F) and its boiling point is at 337.0 °C (610.15 K, 638.6 °F).

Top 10 interesting facts about Astatine

  1. Astatine occurs on Earth as a result of the radioactive decay of other heavier elements.
  2. Astatine is a very radioactive element.
  3. Only less than 1 gram of astatine is found on Earth’s crust at any given time and only six of its isotopes are produced naturally.
  4. Astatine is the second rarest element on Earth’s crust after berkelium.
  5. Astatine does not have stable isotopes. All its 32 isotopes are unstable.
  6. Very little is known about astatine comparing with other elements.
  7. Astatine’s properties are similar to those of iodine making astatine to be considered the heavier brother of iodine.
  8. Astatine has never been viewed by any human since it is vaporized by the heat generated by its own radioactivity.
  9. Chemically, astatine is believed to behave as other halogens.
  10. Astatine-211 is used in medicine to treat some diseases via its emission of alpha particles.

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