Sodium or in Latin, Natrium, has the symbol Na.
Atomic Number = 11, Atomic Mass = 22.98, 11 protons, 11 electrons,
First isolated by Davy in 1807 by the electrolysis of of very
dry molten sodium hydroxide, NaOH.
Most common compounds: sodium chloride (salt), sodium hydroxide,
sodium bicarbonate (baking soda), sodium carbonate.
Chemical Properties: Sodium is a very reactive element and
is never found in the uncombined state in nature. Sodium has
one electron in its outer energy level that is the source of
its chemical reactivity.The most common form found in nature
is salt, NaCl with 2.6 - 3.0% abundance in the earth's crust
and about 3.0% in the ocean.
Sodium metal reacts
spontaneously with water to give sodium hydroxide and hydrogen
gas. The evolution of hydrogen and the exothermic nature of the
reaction may cause it to ignite. Sodium metal normally does not
ignite in air at temperatures below 115 C. But since it is still
very reactive with oxygen, sodium metal is stored under a layer
of mineral oil or kerosene in the lab.