Potassium primarily is found in the muscles and nerves as an ion.
Chunk of potassium metal with peroxides/superoxides (yellow crystals) and ozonide (red coloring) on its surface
Justin Urgitis, www.wikipedia.org
Potassium is important for membrane function, nerve impulses, and muscle contractions. Potassium cations are found in cellular cytoplasm. The electrolyte helps to attract oxygen and remove toxins from the tissues.