19
Potassium
Atomic Number19
Atomic Mass39.098 u
CategoryAlkali Metal
State at Room TempSolid
Year Discovered1807
About Potassium
Essential for heart function, muscle contraction, and nerve signals. Reacts violently with water, producing hydrogen gas that can ignite. Potassium nitrate is the main ingredient in gunpowder. Bananas are famous for potassium but actually contain only moderate amounts. The potassium-40 isotope is naturally radioactive in all potassium-containing foods.
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