Potassium

By John Emsley2011-05-01T00:00:00

Source: Fotolia

Needed by nerves, plants, and spaceships

Potassium is an essential element for almost all living things and we have around 120 g in our body, found mainly in red blood cells, muscles, and the brain.

One of its natural isotopes is potassium-40. This is a β-emitter, converting the nucleus to argon-40 explaining why there is 1% of this gas in the Earth's atmosphere.

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