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Name: Actinium
Symbol: Ac
Number of Energy Levels: 7
Electrons on the outer energy level: 2
Atomic number: 89
Atomic Mass: 227.0 Amu (Atomic Mass Units)
Protons/Electrons: 89
Neutrons: 138
Density: 10.07 g/cm3
Classification: Rare Earth

Actinium | Chemical elements

Actinium was discovered in 1899 by Andre Debierne. Its name derives from the Greek word "aktinos" which means "ray". Actinium’s melting point is at 1050.0 °C (1323.15 K, 1922.0 °F) and its boiling point is at 3200.0 °C (3473.15 K, 5792.0 °F).

Top 10 interesting facts about Actinium

  1. Actinium is a radioactive element.
  2. Actinium is a soft silvery-white metal.
  3. Actinium glows blue in the dark due to its radioactivity.
  4. Actinium has similar chemical properties as lanthanum.
  5. Actinium gave the name to actinide series of elements (15 elements with similar characteristics placed between actinium and lawrencium in periodic table).
  6. Actinium reacts with the oxygen from the air forming a white coating of actinium oxide which prevents further oxidation.
  7. Actinium has a very limited number of compounds.
  8. Actinium has 36 unstable isotopes; two of them occurring naturally.
  9. Actinium is found in very small quantities in uranium and thorium ores.
  10. Actinium is used in very few applications such as neutron source and in medicine for radiation therapy for cancer treatment.

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