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It's Elemental

The Element Sodium

[Click for Isotope Data]


11 Na Sodium 22.98976928

Atomic Number: 11

Atomic Weight: 22.98976928

Melting Point: 370.95 K (97.80°C or 208.04°F)

Boiling Point: 1156 K (883°C or 1621°F)

Density: 0.97 grams per cubic centimeter

Phase at Room Temperature: Solid

Element Classification: Metal

Period Number: 3

Group Number: 1

Group Name: Alkali Metal

What's in a name? From the English word soda and from the Medieval Latin word sodanum, which means "headache remedy." Sodium's chemical symbol comes from the Latin word for sodium carbonate, natrium.

Say what? Sodium is pronounced as SO-dee-em.

History and Uses:

Although sodium is the sixth most abundant element on earth and comprises about 2.6% of the earth's crust, it is a very reactive element and is never found free in nature. Pure sodium was first isolated by Sir Humphry Davy in 1807 through the electrolysis of caustic soda (NaOH). Since sodium can ignite on contact with water, it must be stored in a moisture free environment.

Sodium is used in the production of titanium, sodamide, sodium cyanide, sodium peroxide, and sodium hydride. Liquid sodium has been used as a coolant for nuclear reactors. Sodium vapor is used in streetlights and produces a brilliant yellow light.

Sodium also forms many useful compounds. Some of the most common are: table salt (NaCl), soda ash (Na2CO3), baking soda (NaHCO3), caustic soda (NaOH), Chile saltpeter (NaNO3) and borax (Na2B4O7·10H2O).

Estimated Crustal Abundance: 2.36×104 milligrams per kilogram

Estimated Oceanic Abundance: 1.08×104 milligrams per liter

Number of Stable Isotopes: 1 (View all isotope data)

Ionization Energy: 5.139 eV

Oxidation States: +1

Electron Shell Configuration:


2s2   2p6


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