Sodium is prepared commercially by the electrolytic decomposition of fused sodium chloride. It is a necessary constituent of plant and animal tissue. Sodium in its metallic form is very important in making esters and in the manufacture of organic compounds. Sodium is also a component of table salt, sodium chloride (NaCl) a very important compound found everywhere in the living environment. Its other uses are: to improve the structure of certain alloys; in soap, in combination with fatty acids, in sodium vapor lamps, to descale metals, to purify molten metals. Solid sodium carbonate is needed to make glass. The element is used in the manufacture of tetraethyl lead and as a cooling agent in nuclear reactors. Other important compounds of sodium include sodium carbonate, known as washing soda, and sodium bicarbonate, known as baking soda. Sodium hydroxide, known commercially as soda lye or caustic soda, is used in the manufacture of many important articles of immense importance. Sodium fluoride, NaF, is used as an antiseptic, as a poison for mice and roaches, and in ceramics. Sodium nitrate, known as Chile saltpeter, is used as a fertilizer. Sodium peroxide, Na2O2, is an important bleaching and oxidizing agent. Sodium thiosulfate, Na2S2O3 · 5H2O, known as hypo, is used in photography as a fixing agent.
Sodium (symbol Na, atomic number 11, and atomic weight 22,9898) is a chemical a soft metal, reactive and with a low melting point, and a relative density of 0,97 at 20ºC (68ºF). The element’s name comes from the English word soda, which is sometimes used to describe various sodium compounds. From the commercial point of view, sodium is the most important of all the alkaline metals. Sodium reacts quickly with water, and also with snow and ice, to produce sodium hydroxide and hydrogen. When recently cut metallic sodium is exposed to air, it loses its silvery appearance and acquires an opaque grey colour due to the formation of a sodium oxide coating. While sodium can react with ammonia to form sodium amide, it does react with halogens. Sodium and hydrogen react above 200ºC (390ºF) to form sodium hydride.
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