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Name: Iodine
Symbol: I
Number of Energy Levels: 5
Electrons on the outer energy level: 7
Atomic number: 53
Atomic Mass: 126.904 Amu (Atomic Mass Units)
Protons/Electrons: 53
Neutrons: 74
Density: 4.93 g/cm3
Classification: Halogen

Iodine | Chemical elements

Iodine was discovered in 1811 by Bernard Courtois. Iodine’s name derives from the Greek word "iodes" which means "violet". Iodine’s melting point is at 113.5 °C (386.65 K, 236.3 °F) and its boiling point is at 184.0 °C (457.15 K, 363.2 °F).

Top 15 interesting facts about Iodine

  1. Iodine, under standard conditions, is bluish-black.
  2. Iodine elemental vapor is violet-purple/pink.
  3. Iodine has only one stable isotope, 127-I.
  4. Free iodine occurs naturally as a diatomic molecule I2.
  5. Iodine is preponderantly found on Earth in oceans as iodine ion I-.
  6. Iodine is also found in rocks but in slighter lower concentration.
  7. Iodine is very important for life and has an important biological role.
  8. Iodine deficiency is the main cause of intellectual disabilities.
  9. Iodine’s annually production is about 19,000 tones.
  10. Iodine forms compounds with all elements but not with noble gases.
  11. Chile is the largest producer of iodine (obtained from caliche, a sedimentary rock).
  12. Japan and the USA are the largest producers of iodine from brine (brine is a solution of salt in water).
  13. Iodine and its compounds main use is in nutrition, and the production of acetic acid and different polymers.
  14. Elemental iodine is used as a disinfectant.
  15. Iodine has various uses in medicine.

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