Potassium
Potassium is a chemical element with the symbol K and Atomic-Number 19. Classified as an Alkali-Metal, it is a soft, silvery-white solid that oxidizes rapidly in air and reacts vigorously with water. It was first isolated in 1807 by Humphry-Davy from Caustic-Potash. This element is the seventh most abundant in the Earth's crust. Detailed chemical properties can be explored via the Royal Society of Chemistry.
Biologically, Potassium is an essential Mineral and Electrolyte required for the function of all living cells. It plays a critical role in Nerve-Transmission, Muscle-Contraction, and the maintenance of Fluid-Balance. High dietary intake is associated with a lower risk of Stroke and Hypertension, according to research cited by the World Health Organization. Major food sources include Potatoes, Bananas, and Spinach.