Sodium

Sodium, derived from the mining of sodium chloride, NaCl, ("salt") is used to improve alloys, make organic compounds, such as sodamide and esters, descale metals, purify molten metals, and act as a heat transfer medium, e.g., the NaK alloy.   Sodium compounds are used in the paper, glass, soap, textile, petroleum, chemical, and metal industries.   Sodium compounds are used as a food preservative and as a leveling agent in food processing.   Some important compounds of sodium are the following:

Sodium carbonate or soda ash, Na₂CO₃ , is found in the ashes of many plants.   Pioneer farmers burned cut trees to produce it for sale.   It is produced artificially in large quantities from common salt, NaCl.   It is used in the manufacture of glass, chemicals such as sodium silicates and sodium phosphates, the pulp and paper industries, the manufacture of detergents, and for the treatment of water.   It is also used as an alkaline agent in many chemical industries.   Sodium carbonate, also known as "washing soda" is a water softener used during laundry.   In early America, it was used to wash cotton and wool to woven into textiles.   It combines with the minerals magnesium and calcium in order to keep them from bonding with the detergent being used.   Much sodium carbonate is found naturally today.   Earlier, it was made by the Leblanc process, but this was superseded by the more efficient Solvay process. ^{Wiki n.p.}

Sodium hydroxide (NaOH), also known as lye or caustic soda, is used in industry, mostly as a strong chemical base in the manufacture of paper, textiles, and detergents.   Sodium hydroxide is produced in the chloralkali process, which is the electrolysis of an aqueous solution of sodium chloride.   It is a by-product from the production of chlorine. ^{Wiki n.p.}

Chile saltpeter, NaNO₃, (soda niter) is used to preserve meats and maintain their red color.   It also is used to make potassium nitrate, fertilizers, and explosives.

Di- and tri-sodium phosphates, are used to make detergents, pharmaceuticals, and animal feeds.

Sodium thiosulfate, Na₂SO₃, (sodium hyposulfate, "hypo") is used mainly in photography for developing film.   It is also used in chrome-tanning leather and in chemical manufacture. ^{E'pedia n.p.}

Sodium is essential to animal life and beneficial to plant life.   The sodium cation is the main regulator of the concentration of substances outside cells in animals.   It also aids proper nerve functioning.   Sources: table salt (sodium chloride, NaCl), processed foods.   A deficiency results in greater risks of heart attack.   A lack of sodium causes the body to lose water to maintain a balance of dissolved substances in it, which causes dessication (drying out) of the body and, if prolonged, death.   Too much sodium in the body causes high blood pressure (hypertension), swelling (edema), and heart attacks.   Because modern diets in developed countries contain a high proportion of processed foods, which are high in salt content, excessive sodium intake is a health problem.

Sodium was long known in compounds, but was first isolated by the British chemist, Humphry Davy, in 1807, by electrolysis of caustic soda, NaOH.   This method was superseded by electrolysis of dry, fused sodium chloride, by which it is obtained commercially.   Sodium is the sixth most common element in the earth's crust, about 2.6%.   The most common source of sodium is sodium chloride, NaCl (salt).   Other sources are soda niter (NaNO₃), cryolite, amphibole, zeolite, and sodalite.   Since it is highly reactive, sodium is never found free. ^{Lide 4-27}