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Name: Potassium
Symbol: K
Number of Energy Levels: 4
Electrons on the outer energy level: 1
Atomic number: 19
Atomic Mass: 39.0983 Amu (Atomic Mass Units)
Protons/Electrons: 19
Neutrons: 20
Density: 0.862 g/cm3
Classification: Alkali Metal

Potassium | Chemical elements

Potassium was discovered in 1807 by Sir Humphrey Davy. Its symbol K comes from the Latin word "kalium" and its name derives from the word "potash". Potassium’s melting point is at 63.65 °C (336.8 K, 146.57 °F) and its boiling point is at 774.0 °C (1047.15 K, 425.2 °F).

Top 14 interesting facts about potassium

  1. Potassium is silvery and very soft metal that oxidizes very fast in the air.
  2. Potassium reacts very violently with water.
  3. The reaction with water generates a lot of heat that ignite the hydrogen emitted by the reaction.
  4. Potassium has 24 isotopes but only three of them occur naturally and are stable 39-K, 40-K, and 41-K.
  5. The potassium’s isotope 40-K is radioactive.
  6. In nature, potassium can be found only in ionic salts.
  7. Potassium ions are used by all living cells.
  8. Potassium is very less dense; only lithium is lesser dense than potassium.
  9. Potassium reacts very easy with oxygen forming potassium peroxide and with hydrogen forming potassium hydroxide.
  10. Potassium is created by the type 2 supernovas.
  11. Potassium represents 2.6% of the Earth’s crust.
  12. It is the 7th most abundant element in the Earth’s crust, 17th most abundant in entire planet and 20th most abundant in our solar system.
  13. Potassium is used as a fertilizer in agriculture.
  14. Potassium is an important nutrient in human life so it has many applications in food industry.

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