Information AboutSulfur |
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Sulfur or '''sulphur''' () is the Chemical Element that has the symbol '''S''' and Atomic Number 16. It is an abundant, tasteless, Multivalent Non-metal . Sulfur, in its native form, is a yellow crystalline solid. In Nature , it can be found as the pure element or as Sulfide and Sulfate minerals. It is an essential element for life and is found in two Amino Acid s, Cysteine and Methionine . Its commercial uses are primarily in Fertilizer s, but it is also widely used in Gunpowder , Match es, Insecticide s and Fungicide s. NOTABLE CHARACTERISTICS At room temperature, sulfur is a soft bright yellow solid. Elemental sulfur has only a faint odor similar to that of Matches . The odor associated with rotten eggs is from Hydrogen Sulfide (H2S) and organic sulfur compounds. Sulfur burns with a blue flame that emits Sulfur Dioxide , notable for its peculiar suffocating odor. Sulfur is insoluble in water but Soluble in Carbon Disulfide and to a lesser extent in other nonpolar organic solvents such as Benzene and Toluene . Common Oxidation State s of sulfur include −2, +2, +4 and +6. Sulfur forms stable compounds with all elements except the Noble Gas es. Sulfur in the solid state ordinarily exists as cyclic crown-shaped S8 molecules. Sulfur has many , the heavier analogue of sulfur can form rings but is more often found as a polymer chain. The Crystallography of sulfur is complex. Depending on the specific conditions, the sulfur Allotrope s form several distinct Crystal Structure s, with Rhombic and ''' Monoclinic ''' S8 best known. A noteworthy property of sulfur is that its Viscosity in its molten state, unlike most other liquids, increases above temperatures of 200°C due to the formation of Polymer chains. The molten sulfur also becomes dark red in colour above this temperature due to the presence of free valences on terminal atoms of the polymer chains. However, after a specific temperature is reached, the viscosity is reduced because there is enough energy to break the chains. Amorphous or "plastic" sulfur can be produced through the rapid cooling of molten sulfur. X-ray Crystallography studies show that the amorphous form may have a Helical structure with eight atoms per turn. This form is Metastable at room temperature and gradually reverts back to crystalline form. This process happens within a matter of hours to days but can be rapidly catalyzed. APPLICATIONS In the late 1700s , Furniture makers used molten sulfur to produce decorative Inlay s in their craft. Because of the Sulfur Dioxide produced during the process of melting sulfur, the craft of sulfur inlays was soon abandoned. Molten sulfur is sometimes still used for setting steel bolts into drilled concrete holes where high shock resistance is desired for floor-mounted equipment attachment points. Pure powdered sulfur was also used as a medicinal tonic and laxative. Sulfur has many modern industrial uses. Through its major derivative, Sulfuric Acid ( H 2S O 4), sulfur ranks as one of the most important industrial raw materials. It is of prime importance to every sector of the World's Economies . Sulfuric acid production is the major route in industrial sulfur chemistry on the way to many end-uses, and production and consumption of sulfuric acid has been regarded as one of the best indices of a nation's industrial development. {Link without Title} . For example, more sulfuric acid is produced in the United States every year than any other industrial chemical; although interestingly the rate of increase of U.S. production has encountered shocks since the mid 1960's, mirroring U.S. loss of industrial post- World War II world influence. Principal uses for the acid include ore processing, fertilizer manufacturing, oil refining, wastewater processing, and chemical synthesis. Sulfur is also used in Batteries , Detergents , the Vulcanization of rubber, Fungicide s, ie skin care soaps, and in the manufacture of Phosphate fertilizers. Sulfite s are used to Bleach Paper and as a preservative in Wine and dried Fruit . Because of its flammable nature, sulfur also finds use in Match es, Gunpowder , and Firework s. Sodium or ammonium Thiosulfate is used as photographic fixing agents. Magnesium Sulfate , better known as Epsom Salts , can be used as a Laxative , a bath additive, an Exfoliant , a Magnesium supplement for plants, or a Desiccant . Sulfur is used as a light-generating medium in the rare lighting fixtures known as Sulfur Lamp s. Elemental sulfur crystals are commonly sought after by rock collectors for their brightly colored Polyhedron shapes. BIOLOGICAL ROLE Sulfur is an essential component of all living Cells . Sulfur may also serve as chemical food source for some primitive organisms: some forms of Bacteria use Hydrogen Sulfide (H2S) in the place of water as the Electron donor in a primitive Photosynthesis -like process. Inorganic sulfur forms a part of Iron-sulfur Cluster s, and sulfur is the bridging ligand in the Cu A site of Cytochrome C Oxidase , a basic substance involved in utilization of oxygen by all aerobic life. Sulfur is absorbed by Plant s via the Root s from soil as the Sulfate Ion and reduced to sulfide before it is incorporated into Cysteine and other organic sulfur compounds ( Sulfur Assimilation ). In and Alpha-lipoic Acid . Disulfide Bond s (S-S bonds) formed between cysteine residues in peptide chains are very important in protein assembly and structure. These strong covalent bonds between peptide chains give proteins a great deal of extra toughness and resiliency. For example, the high strength of feathers and hair is in part due to their high content of S-S bonds and their high content of cysteine and sulfur (eggs are high in sulfur because large amounts of the element are necessary for feather formation). The high disulfide content of hair and feathers also contributes to their indigestibility, and also their smelly odor when burned. ENVIRONMENTAL IMPACT The burning of Coal and/or Petroleum by industry and Power Plants creates massive amounts of Sulfur Dioxide (S O 2) which reacts with atmospheric water and oxygen to produce Sulfuric Acid (H2SO4). This sulfuric acid is a component of Acid Rain , which lowers the PH of Soil and freshwater bodies, resulting in substantial damage to the Natural Environment and Chemical Weathering of statues and structures. Fuel standards increasingly require sulfur to be extracted from Fossil Fuel s to prevent the formation of acid rain. This extracted sulfur is then refined and represents a large portion of sulfur production. HISTORY , Italy ]] Sulfur ( Sanskrit , ''sulvari''; Latin ''sulfur'' or ''sulpur'') was known in ancient times, and is referred to in the Biblical Pentateuch ( Genesis ). The word itself probably is from the Arabic ''sufra'' meaning yellow, from the bright color of the naturally occurring form, although the Sanskrit name for sulfur, ''sulvari'' could also be interpreted as meaning "enemy of copper". English translations of the Bible commonly refer to sulfur as "brimstone", giving rise to the name of 'Fire and brimstone' Sermon s, in which listeners are reminded of the fate of eternal damnation that awaits the nonbelieving and unrepented. It is from this part of the Bible that Hell is implied to "smell of sulfur", although as mentioned above sulfur is in fact odorless. The "smell of sulfur" usually refers to the odor of Hydrogen Sulfide , e.g. from rotten eggs. Burning sulfur produces Sulfur Dioxide , the smell associated with burnt matches. Homer mentioned "pest-averting sulfur" in the 8th Century BC and in 424 BC , the tribe of Boeotia destroyed the walls of a city by burning a mixture of coal, sulfur, and tar under them . Sulfur was known in China since the 6th century BC, in a natural form that the Chinese had called 'brimstone', or ''shiliuhuang'' that was found in Hanzhong .1 By the 3rd century, the Chinese discovered that sulfur could be extracted from Pyrite . Chinese Daoists were interested in sulfur's flammability and its reactivity with certain metals, yet its earliest practical uses were found in Traditional Chinese Medicine . A Song Dynasty military treatise of 1044 AD described different formulas for Chinese Gun Powder , which is a mixture of Potassium Nitrate ( K N O 3), Carbon , and sulfur. Early Alchemists gave sulfur its own Alchemical Symbol which was a triangle at the top of a cross. In the late 1770s , Antoine Lavoisier helped convince the scientific community that sulfur was an element and not a compound. In 1867, sulfur was discovered in underground deposits in Louisiana and Texas . The overlying layer of earth was Quicksand , prohibiting ordinary mining operations. Therefore the Frasch Process was utilized. OCCURRENCE Hot Springs , New Zealand ]] , stockpiled for shipment at Vancouver, B. C. ]] Elemental sulfur can be found near Hot Spring s and Volcanic regions in many parts of the world, especially along the Pacific Ring Of Fire . Such volcanic deposits are currently mined in Indonesia , Chile , and Japan . Sicily is also famous for its sulfur mines. Significant deposits of elemental sulfur also exist in Salt Domes along the coast of the Gulf Of Mexico , and in Evaporite s in eastern Europe and western Asia. The sulfur in these deposits is believed to come from the action of Anaerobic Bacteria on Sulfate Minerals , especially Gypsum , although apparently native sulfur may be produced by geological processes alone, without the aid of living organisms (see below). However, fossil-based sulfur deposits from salt domes are the basis for commercial production in the United States , Poland , Russia , Turkmenistan , and Ukraine . Sulfur production through Hydrodesulfurization of oil, gas, and the Athabasca Oil Sands has produced a surplus - huge stockpiles of sulfur now exist throughout Alberta, Canada. Common naturally occurring sulfur compounds include the Sulfide Minerals , such as Pyrite (iron sulfide), Cinnabar (mercury sulfide), Galena ( Lead Sulfide ), Sphalerite (zinc sulfide) and Stibnite (antimony sulfide); and the sulfates, such as gypsum (calcium sulfate), Alunite (potassium aluminium sulfate), and Barite (barium sulfate). It occurs naturally in volcanic emissions, such as from Hydrothermal Vent s, and from bacterial action on decaying sulfur-containing organic matter. The distinctive colors of Jupiter 's Volcanic moon, Io , are from various forms of molten, solid and gaseous sulfur. There is also a dark area near the Lunar Crater Aristarchus that may be a sulfur deposit. Sulfur is also present in many types of Meteorite s. EXTRACTION Sulfur is extracted by mainly two processes: the Sicilian process and the Frasch Process . The Sicilian process, which was first used in Sicily , was utilized in ancient times to get sulfur from rocks present in volcanic regions. In this process, the sulfur deposits are piled and stacked in brick kilns built on sloping hillsides, and with airspaces between them. Then powdered sulfur is put on top of the sulfur deposit and lit on fire. As the sulfur burns it produces heat, which melts the sulfur deposits, causing the molten sulfur to flow down the sloping hillsides. The molten sulfur can then be collected in wooden buckets. The second process used to obtain sulfur is the Frasch process. In this method, three concentric pipes are used: The outermost pipe contains superheated water, which melts the sulfur, and the innermost pipe is filled with hot compressed air, which serves to create foam and pressure. The resulting sulfur foam is then expelled out through the middle pipe. The Frasch process produces sulfur with a 99.5% purity content, and which needs no further purification. On the other hand, the sulfur produced by the Sicilian process must be purified by distillation. COMPOUNDS Hydrogen Sulfide has the characteristic smell of rotten eggs. Dissolved in water, hydrogen sulfide is acidic and will react with metals to form a series of metal sulfides. Natural metal sulfides are common, especially those of iron. Iron sulfide is called Pyrite , the so-called ''fool's gold''. Interestingly, pyrite can show semiconductor properties.2 Galena , a naturally occurring lead sulfide, was the first Semiconductor discovered, and found a use as a signal Rectifier in the "cat's whiskers" of early Crystal Radio s. Many of the unpleasant odors of organic matter are based on sulfur-containing compounds such as Methyl and Ethyl Mercaptan used to scent natural gas so that leaks are easily detectable. The odor of Garlic and " Skunk stink" are also caused by sulfur-containing organic compounds. However, not all organic sulfur compounds smell unpleasant; for example, Grapefruit Mercaptan , a sulfur-containing Monoterpenoid is responsible for the characteristic scent of Grapefruit . Polymeric sulfur nitride has metallic properties even though it does not contain any Metal atoms. This compound also has unusual electrical and optical properties. This polymer can be made from Tetrasulfur Tetranitride S4N4. Phosphorus sulfides are important in synthesis. For example, P4S10 and its derivatives Lawesson's Reagent and Naphthalen-1,8-diyl 1,3,2,4-dithiadiphosphetane 2,4-disulfide are used to replace oxygen from some organic molecules with sulfur. Inorganic sulfur compounds:
Organic sulfur compounds (where R, R', and R'' are organic groups such as CH3): ]]
''See also and Organosulfur Chemistry '' ISOTOPES See Also: Isotopes of sulfur Sulfur has 18 of sulfur are all short lived. 35S is formed from Cosmic Ray Spallation of 40 Ar in the Atmosphere . It has a Half-life of 87 days. When sulfide Mineral s are precipitated, isotopic equilibration among solids and liquid may cause small differences in the δS-34 values of co-genetic minerals. The differences between minerals can be used to estimate the temperature of equilibration. The δ C -13 and δS-34 of coexisting Carbonate s and sulfides can be used to determine the PH and Oxygen Fugacity of the ore-bearing fluid during ore formation. In most Forest ecosystems, sulfate is derived mostly from the atmosphere; weathering of ore minerals and evaporites also contribute some sulfur. Sulfur with a distinctive isotopic composition has been used to identify pollution sources, and enriched sulfur has been added as a tracer in Hydrologic studies. Differences in the Natural Abundance s can also be used in systems where there is sufficient variation in the 34S of ecosystem components. Rocky Mountain lakes thought to be dominated by atmospheric sources of sulfate have been found to have different δS-34 values from lakes believed to be dominated by watershed sources of sulfate. PRECAUTIONS Carbon disulfide, carbon oxysulfide, hydrogen sulfide, and sulfur dioxide should all be handled with care. Although '' Sulfur Dioxide '' is sufficiently safe to be used as a Food Additive in small amounts, at high concentrations it reacts with moisture to form Sulfurous Acid which in sufficient quantities may harm the Lungs , Eyes or other Tissues . In organisms without lungs such as insects or plants, it otherwise prevents Respiration . '' Hydrogen Sulfide '' is quite Toxic (more toxic than Cyanide ). Although very pungent at first, it quickly deadens the sense of smell, so potential victims may be unaware of its presence until it is too late. SPELLING The element has traditionally been spelled ''sulphur'' in the United Kingdom , Ireland , Hong Kong , the Commonwealth Caribbean and India , but ''sulfur'' in the United States , while both spellings are used in Australia , Canada and New Zealand . IUPAC adopted the spelling “sulfur” in 1990, as did the Royal Society Of Chemistry Nomenclature Committee in 1992. The spelling of the term in non-official texts is gradually becoming uniform as ''sulfur''. The Latin name of the element is ''sulfur'' with an F. Since it is an original Latin name and not a Classical Greek loan, the fricative phoneme is indeed denoted with ''f'' rather than ''ph'' (which would denote the Greek letter φ). Sulfur in Greek is ''theion'' (θεῖον), whence comes the prefix Thio- . SEE ALSO
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