Potassium is a silvery-white metallic element that oxidizes rapidly in the air and whose compounds are used as fertilizer and in special hard glasses. It has the symbol K and atomic number 19. It is very reactive with water.
The English name for the element potassium comes from the word "potash", referring to the method by which potash was obtained – leaching the ash of burnt wood or tree leaves and evaporating the solution in a pot. Potash is primarily a mixture of potassium salts.
Potassium as nutrient for plants
Boron as nutrient in food
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