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Name: Chlorine
Symbol: Cl
Number of Energy Levels: 3
Electrons on the outer energy level: 7
Atomic number: 17
Atomic Mass: 35.4527 Amu (Atomic Mass Units)
Protons/Electrons: 17
Neutrons: 18
Density: 3.214 g/cm3
Classification: Halogen

Chlorine | Chemical elements

Chlorine was discovered in 1774 by Carl Wilhelm Scheele. Its name derives from the Greek word "khloros" which means "green". Chlorine is obtained from salt and it is mainly used in water purification, public sanitation, disinfection, and antisepsis.

Top 13 interesting facts and information about chlorine

  1. Under standard conditions chlorine is a gas having a yellow-green color.
  2. Chlorine has the highest electron affinity so it is very reactive; as a result, elemental chlorine rarely can be found on Earth.
  3. Chlorine is the 21st most abundant element in the Earth crust but the 2nd most abundant halogen.
  4. Elemental chlorine was used in the First World War as a chemical weapon.
  5. Boiling point of chlorine is at -34.6 °C (238.55 K, -30.279997 °F) and melting point at -100.98 °C (172.17 K, -149.764 °F).
  6. Chlorine reacts with the majority of the elements of the Mendeleev periodic table forming compounds called chlorides (in most situations).
  7. Chlorine is formed in supernovae.
  8. Humans know more than two thousand chlorine compounds that occur naturally.
  9. Chlorine has many isotopes but the stable isotopes are Cl-35 and Cl-37.
  10. Chlorine is obtained from sodium chloride through the electrolysis process.
  11. Chlorine is used in production of plastics, solvents for cleaning and degreasing, textiles, pharmaceuticals, insecticides, different cleaning products, and many more.
  12. Chlorine gas is heavier than the air.
  13. One of the most powerful pain killer, that is a chlorine compound, is found in the skin of the tree frog.

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