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Name: Oxygen
Symbol: O
Number of Energy Levels: 2
Electrons on the outer energy level: 6
Atomic number: 8
Atomic Mass: 15.9994 Amu (Atomic Mass Units)
Protons/Electrons: 8
Neutrons: 8
Density: 1.429 g/cm3
Classification: Non-Metal

Oxygen | Chemical elements

Top 16 interesting facts about oxygen

  1. Oxygen is a highly reactive element forming compounds very fast with most of the other elements.
  2. Oxygen is the third most abundant element in the universe after Hydrogen and Helium.
  3. Oxygen at standard temperature and pressure is a diatomic gas with the formula O2 that is colorless, odorless, and tasteless.
  4. Since oxygen is part of the water, it is a major constituent of the mass of living organisms.
  5. Oxygen represents 20.8% of the volume of the air.
  6. Because oxygen reacts with so many other elements and forms compounds very easy, oxygen is the most abundant element on Earth by mass as part of oxide compounds.
  7. Elemental oxygen is produced by plants and different algae and all complex forms of life use it for respiration.
  8. Ozone is another form of Oxygen (O3), formed by three atoms of Oxygen, which protects the Earth from ultra-violet radiation emitted by Sun (but not only).
  9. Oxygen is produced industrially from liquefied air, electrolysis of water, etc and it is used in steel and plastic production, welding and cutting metals, life support system on aircrafts, etc.
  10. Oxygen was discovered by Carl Wilhelm Scheele in 1773.
  11. Oxygen condenses at −182.95 °C (−297.31 °F). Liquid Oxygen is a very reactive substance.
  12. Oxygen freezes at −218.79 °C (−361.82 °F).
  13. Almost 1 percent (0.9%) of the mass of the Sun is Oxygen.
  14. Without Oxygen conventional combustion wouldn’t be possible.
  15. Aurora Borealis is formed by the excited Oxygen from the atmosphere.
  16. Oxygen is used in medicine for different therapies.

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