potassium vs. sodium

potassium

noun

Chemistry.

  1. a silvery-white metallic element that oxidizes rapidly in the air and whose compounds are used as fertilizer and in special hard glasses. K; 39.102; 19; 0.86 at 20°C.

sodium

noun

  1. Chemistry.,  a soft, silver-white, metallic element that oxidizes rapidly in moist air, occurring in nature only in the combined state, and used in the synthesis of sodium peroxide, sodium cyanide, and tetraethyllead: a necessary element in the body for the maintenance of normal fluid balance and other physiological functions. Na; 22.9898; 11; 0.97 at 20°C.

  2. Medicine/Medical, Pharmacology.,  any salt of sodium, as sodium chloride or sodium bicarbonate, present in or added to foods or beverages as a seasoning or preservative and used in many pharmaceutical products as an antacid, anticoagulant, or other agent.