Potassium

Potassium 39.0983(1)   K 19 1s22s22p63s23p64s1 1,4,s [ ? ] Alkali metal: Properties: Soft, silvery-white metal. Uses: Major use is in fertilizer industry.

Potassium is a chemical element, having the chemical symbol K. Its atomic number (the number of protons) is 19. It has a standard atomic weight of 39.0983 g•mol ⁻¹, and is typically found as a solid in its elemental form.

Potassium is considered to be a member of the "alkali metal" class of element. At a pressure of 101.325 kPa, it has a boiling point of 769 °C, and a melting point of 65.5 °C. It is a silvery-white, reactive metal. Potassium reacts violently with water, producing hydrogen. With a density of 0.862 g/cc, potassium is less dense than water.

Potassium in its cation form (K⁺) performs many different functions within the human body. K⁺ is essential for cellular function and maintaining homeostasis through action potentials.

Biochemistry

Potassium is a vital ion in cellular communication via the action potential.

Hyperkalemia occurs when there is too much potassium in the blood, and hypokalemia when there is a deficiency. Potassium levels in the body are balanced by levels of sodium.