Sodium

Sodium 22.989770(2)   Na 11 1s22s22p63s1 1,3,s [ ? ] Alkali metal: Properties: Soft, bright, silvery metal. Reactive. Hazard: Potentially explosive. Store in dry, inert, oxygen-free atmosphere.

Sodium is a chemical element, having the chemical symbol Na. Its atomic number (the number of protons) is 11. It has a standard atomic weight of 22.98977 g•mol ⁻¹, and is typically found as a solid in its elemental form.

Sodium 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 883 °C, and a melting point of 97.8 °C. In solid form, its density is slightly less than that of water at 0.968 g/cc.

It is easily oxidized to the +1 oxidation state and forms many salts. Elevated sodium levels in humans may lead to high blood pressure and other complications. The pure metal reacts violently with water.