| Sodium (symbol Na, atomic number 11, and atomic | | | | hydroxide, known commercially as soda lye or caustic |
| weight 22,9898) is a chemical a soft metal, reactive | | | | soda, is used in the manufacture of many important |
| and with a low melting point, and a relative density of | | | | articles of immense importance. Sodium fluoride, NaF, |
| 0,97 at 20ºC (68ºF). The element’s name | | | | is used as an antiseptic, as a poison for mice and |
| comes from the English word soda, which is | | | | roaches, and in ceramics. Sodium nitrate, known as |
| sometimes used to describe various sodium | | | | Chile saltpeter, is used as a fertilizer. Sodium peroxide, |
| compounds. From the commercial point of view, | | | | Na2O2, is an important bleaching and oxidizing agent. |
| sodium is the most important of all the alkaline | | | | Sodium thiosulfate, Na2S2O3 · 5H2O, known as |
| metals. Sodium reacts quickly with water, and also | | | | hypo, is used in photography as a fixing agent. |
| with snow and ice, to produce sodium hydroxide and | | | | Sodium is the most abundant element in the |
| hydrogen. When recently cut metallic sodium is | | | | Earth’s crust and is found in nature only in the |
| exposed to air, it loses its silvery appearance and | | | | combined state ranking sixth or seventh in order of |
| acquires an opaque grey colour due to the formation | | | | abundance of the elements and containing 2,83% of |
| of a sodium oxide coating. While sodium can react | | | | sodium in all its forms. It occurs in the ocean and in |
| with ammonia to form sodium amide, it does react | | | | salt lakes as sodium chloride, NaCl, and less often as |
| with halogens. Sodium and hydrogen react above | | | | sodium carbonate, Na2CO3, and sodium sulfate, |
| 200ºC (390ºF) to form sodium hydride. | | | | Na2SO4. Sodium is the second most abundant |
| Sodium also reacts with various metallic halides to | | | | element after chlorine (as chloride ions) dissolved in |
| generate the metal and sodium chloride. Sodium | | | | seawater. The most important sodium salts found in |
| doesn’t react with paraffinic hydrocarbons, but it | | | | nature are sodium chloride (halite or rock salt), sodium |
| forms addition compounds with naphthalene and | | | | carbonate (trona or soda), sodium borate (borax), |
| other aromatic polycyclic compounds and with aryl | | | | sodium nitrate and sodium sulfate. Sodium salts are |
| alkenes. The reaction of sodium with alcohols is similar | | | | found in seawater (1.05%), salty lakes, alkaline lakes |
| to the reaction of sodium with water, but slower. | | | | and springs. A huge amount of this salt is extracted |
| There are two general reactions with organic halides. | | | | mainly from salt deposits by pumping water down |
| One of them requires the condensation of two | | | | bore holes to dissolve it and pumping up brine. The |
| organic compounds, which form halogens when those | | | | sun and many other stars shine with visible light in |
| are eliminated. The second type of reaction includes | | | | which the yellow component dominates and this is |
| the replacement of halogen by sodium, to obtain a | | | | given out by sodium atoms in a high-energy state. |
| sodium organic compound. Sodium is found in nature | | | | Sodium's powdered form is highly explosive in water |
| only in the combined state. It occurs in the ocean | | | | and a poison combined and uncombined with many |
| and in salt lakes as sodium chloride, NaCl, and less | | | | other elements. This chemical is not mobile in solid |
| often as sodium carbonate, Na2CO3, and sodium | | | | form, although it absorbs moisture very easily. |
| sulfate, Na2SO4. Sodium is prepared commercially by | | | | Sodium salts are important ingredients of many |
| the electrolytic decomposition of fused sodium | | | | foodstuffs (for instance common salt) as besides |
| chloride. Sodium ranks seventh in order of abundance | | | | imparting salty taste, it is necessary for humans to |
| of the elements in Earth's crust. It is a necessary | | | | maintain the balance of the physical fluids system. |
| constituent of plant and animal tissue. | | | | Sodium is also required for nerve and muscle |
| Sodium is prepared commercially by the electrolytic | | | | functioning. However, too much sodium can damage |
| decomposition of fused sodium chloride. It is a | | | | our kidneys and increases the chances of high blood |
| necessary constituent of plant and animal tissue. | | | | pressure. The amount of sodium a person consumes |
| Sodium in its metallic form is very important in making | | | | each day varies from individual to individual and from |
| esters and in the manufacture of organic compounds. | | | | culture to culture. Some people get as little as 2 g |
| Sodium is also a component of table salt, sodium | | | | day, some as much as 20 grams. Sodium is essential, |
| chloride (NaCl) a very important compound found | | | | but controversially surrounds the amount required. |
| everywhere in the living environment. Its other uses | | | | Contact of sodium with water, including perspiration |
| are: to improve the structure of certain alloys; in | | | | causes the formation of sodium hydroxide fumes, |
| soap, in combination with fatty acids, in sodium vapor | | | | which are highly irritating to skin, eyes, nose and |
| lamps, to descale metals, to purify molten metals. | | | | throat. This may cause sneezing and coughing. Very |
| Solid sodium carbonate is needed to make glass. The | | | | severe exposures may result in difficult breathing, |
| element is used in the manufacture of tetraethyl lead | | | | coughing and chemical bronchitis. Contact to the skin |
| and as a cooling agent in nuclear reactors. Other | | | | may cause itching, tingling, thermal and caustic burns |
| important compounds of sodium include sodium | | | | and permanent damage. Its contact with eyes may |
| carbonate, known as washing soda, and sodium | | | | result in permanent damage and loss of sight. |
| bicarbonate, known as baking soda. Sodium | | | | |