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Name: Neptunium
Symbol: Np
Number of Energy Levels: 7
Electrons on the outer energy level: 2
Atomic number: 93
Atomic Mass: 237 Amu (Atomic Mass Units)
Protons/Electrons: 93
Neutrons: 144
Density: 20.45 g/cm3
Classification: Rare Earth

Neptunium | Chemical elements

Neptunium was discovered in 1940 by Edwin McMillan and Phillip H. Abelson. Its name derives from the name of the planet Neptune. Neptunium’s melting point is at 640.0 °C (913.15 K, 1184.0 °F) and its boiling point is at 3902.0 °C (4175.15 K, 7055.6 °F).

Top 10 interesting facts about Neptunium

  1. Neptunium is a ductile, hard, and radioactive metal.
  2. Neptunium is a fissionable element.
  3. Neptunium has a silvery color and tarnishes in the air.
  4. Most of neptunium is produced in nuclear reactors as a by-product.
  5. Neptunium is also found in uranium ores in very small amounts as a decay product of other isotopes.
  6. All neptunium’s isotopes are unstable and the most stable isotope of neptunium is 237-neptunium.
  7. Neptunium is used in detectors of high-energy neutrons.
  8. Neptunium is used as a precursor in plutonium production.
  9. Neptunium could be used as fuel for fast neutron reactors and in nuclear weapons.
  10. Neptunium does not have any biological role.

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