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Name: Calcium
Symbol: Ca
Number of Energy Levels: 4
Electrons on the outer energy level: 2
Atomic number: 20
Atomic Mass: 40.078 Amu (Atomic Mass Units)
Protons/Electrons: 20
Neutrons: 20
Density: 1.55 g/cm3
Classification: Alkaline Earth

Calcium | Chemical elements

Calcium was discovered in 1808 by Sir Humphrey Davy. Its name derives from the Latin word "calcis" which means "lime".

Top 19 interesting facts about calcium

  1. Calcium is the 5th most abundant element in Earth’s crust by mass and dissolved in sea-water.
  2. Calcium is essential element in bones, teeth, and shells.
  3. Calcium is a soft grey/silvery metal.
  4. Calcium is the most abundant metal by mass in many living organisms.
  5. Calcium is considered a reactive element.
  6. Calcium is soft enough to be cut with a knife.
  7. It is mainly extracted by electrolysis from calcium chloride.
  8. Calcium reacts with air forming a grey oxide and nitride coating.
  9. Calcium also reacts with water fast enough to be noticeable producing hydrogen gas.
  10. Calcium is the lightest among Alkaline Earth metals.
  11. Calcium has six stable isotopes 40-Ca, 42-Ca, 43-Ca, 44-Ca, 46-Ca, and 48-Ca.
  12. The calcium isotope 40-Ca represents 97% of the naturally occurring calcium.
  13. Calcium is used as a reduction agent in the extraction of other metals.
  14. Calcium is used as a deoxidizer, desulfurizer, and decarbonizer for various alloys.
  15. Calcium is used in the production aluminum alloys (and many other alloys) as an alloying agent.
  16. Calcium is used in construction industry for making cements and mortars.
  17. Calcium is used in food industry in making of cheese as a milk coagulator.
  18. About 99% of the calcium found in human body is stored in bones.
  19. China, the USA, and India are the biggest producers of calcium.

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