Sodium

Sodium is a soft, silvery-white alkali metal that conducts heat and electricity well. It reacts readily with air and water, so it occurs naturally in compounds rather than as pure metal. Sodium is abundant in seawater as dissolved ions and in minerals such as halite, the mineral form of sodium chloride, or common salt. Industry obtains sodium metal by using electricity to break down molten sodium chloride, a process called electrolysis. Sodium vapor produces the distinctive yellow glow of some streetlights. In your body, sodium ions help nerve cells transmit signals. These charged particles, also present in table salt, have very different properties from the reactive metal.