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20 décembre 2011 2 20 /12 /décembre /2011 02:35

Compounds and chemistry

In the great majority of its compounds, tin has the oxidation state II or IV.Sony VAIO VGN-NW91FS Battery

Inorganic compounds

Halide compounds are known for both oxidation states. For Sn(IV), all four halides are well known: SnF4, SnCl4, SnBr4, and SnI4. The three heavier members are volatile molecular compounds, whereas the tetrafluoride is polymeric. All four halides are known for Sn(II) also: SnF2, SnCl2, SnBr2, and SnI2. All are polymeric solids. Of these eight compounds, only the iodides are coloured.Sony VAIO VGN-NW91GS Battery

Tin(II) chloride (also known as stannous chloride) is the most important tin halide in a commercial sense. Illustrating the routes to such compounds, chlorine reacts with tin metal to give SnCl4 whereas the reaction of hydrochloric acid and tin gives SnCl2 and hydrogen gas. Alternatively SnCl4 and Sn combine to stannous chloride via a process called comproportionationSony VAIO VGN-NW91VS Battery

SnCl4 + Sn ? 2 SnCl2

Tin can form many oxides, sulfides, and other chalcogenide derivatives. The dioxide SnO2 (cassiterite) forms when tin is heated in the presence of air. SnO2 isamphoteric, which means that it dissolves in both acidic and basic solutions. There are also stannates with the structure [Sn(OH)6]2?, like K2[Sn(OH)6], although the free stannic acid H2[Sn(OH)6] is unknown.Sony VAIO VGN-SR11M Battery

The sulfides of tin exist in both the +2 and +4 oxidation states: tin(II) sulfide and tin(IV) sulfide (Mosaic gold).

Hydrides

Stannane (SnH4), where tin is in the +4 oxidation state, is unstable. Organotin hydrides are however well known, e.g. tributyltin hydride (Sn(C4H9)3H). These compound release transient tributyl tin radicals, rare examples of compounds of tin(III).Sony VAIO VGN-SR11MR Battery

Organotin compounds

Organotin compounds, sometimes called stannanes, are chemical compounds with tin-carbon bonds. Of the compounds of tin, the organic derivatives are the most useful commercially. Some organotin compounds are highly toxic and have been used as biocides.Sony VAIO VGN-SR140D Battery

The first organotin compound to be reported was diethyltin diiodide ((C2H5)2SnI2), reported byEdward Frankland in 1849.

Most organotin compounds are colorless liquids or solids that are stable to air and water. They adopt tetrahedral geometry. Tetraalkyl- and tetraaryltin compounds can be prepared usingGrignard reagents:Sony VAIO VGN-SR140D/B Battery

SnCl4 + 4 RMgBr ? R4Sn + 4 MgBrCl

The mixed halide-alkyls, which are more common and more important commercially than the tetraorgano derivatives, are prepared by redistribution reactions:

SnCl4 + R4Sn ? 2 SnCl2R2

Divalent organotin compounds are uncommon, although more common than related divalent organogermanium and organosilicon compounds.Sony VAIO VGN-SR140D/P Battery

The greater stabilization enjoyed by Sn(II) is attributed to the "inert pair effect". Organotin(II) compounds include both stannylenes (formula: R2Sn, as seen for singlet carbenes) and distannylenes (R4Sn2), which are roughly equivalent to alkenes. Both classes exhibit unusual reactions.Sony VAIO VGN-SR140D/S Battery

Occurrence

Tin is generated via the long S-process in low-medium mass stars (with masses of 0.6 to 10 of that of Sun). It arises via beta decay of heavy isotopes of indium.

Tin is the 49th most abundant element in the Earth's crust, representing 2 ppm compared with 75 ppm for zinc, 50 ppm for copper, and 14 ppm for lead.Sony VAIO VGN-SR140E Battery

Tin does not occur as the native element but must be extracted from various ores. Cassiterite (SnO2) is the only commercially important source of tin, although small quantities of tin are recovered from complex sulfides such as stannite, cylindrite, franckeite, canfieldite, andteallite. Minerals with tin are almost always associated with granite rock, usually at a level of 1% tin oxide content.Sony VAIO VGN-SR140E/B Battery

Because of the higher specific gravity of tin dioxide, about 80% of mined tin is from secondary deposits found downstream from the primary lodes. Tin is often recovered from granules washed downstream in the past and deposited in valleys or under sea. The most economical ways of mining tin are through dredging, hydraulic methods or open cast mining.Sony VAIO VGN-SR140E/P Battery

Most of the world's tin is produced from placer deposits, which may contain as little as 0.015% tin.

It was estimated in January 2008 that there were 6.1 million tons of economically recoverable primary reserves, from a known base reserve of 11 million tons. Below are listed the nations with the largest known reserves.Sony VAIO VGN-SR140E/S Battery

Estimates of tin production have historically varied with the dynamics of economic feasibility and the development of mining technologies, but it is estimated that, at current consumption rates and technologies, the Earth will run out of tin that can be mined in 40 years.Sony VAIO VGN-SR140N/S Battery

However Lester Brown has suggested tin could run out within 20 years based on an extremely conservative extrapolation of 2% growth per year.

Secondary, or scrap, tin is also an important source of the metal. The recovery of tin through secondary production, or recycling of scrap tin, is increasing rapidly.Sony VAIO VGN-SR165E/B Battery

Whereas the United States has neither mined since 1993 nor smelted tin since 1989, it was the largest secondary producer, recycling nearly 14,000 tons in 2006.

New deposits are reported to be in southern Mongolia, and in 2009, new deposits of tin were discovered in Colombia, South America, by the Seminole Group Colombia CI, SAS.Sony VAIO VGN-SR165E/P Battery

Production

Tin is produced by reducing the ore with carbon in a reverberatory furnace.

Mining and smelting

In 2006, total worldwide tin mine production was 321,000 tons, and smelter production was 340,000 tons. From its production level of 186,300 tons in 1991, around where it had hovered for the previous decades, production of tin increased 89% to 351,800 tons in 2005.Sony VAIO VGN-SR165E/S Battery

Most of the increase came from China and Indonesia, with the largest spike in 2004–2005, when it increased 23%. While in the 1970s Malaysia was the largest producer, with around a third of world production, it has steadily fallen, and now remains a major smelter and market center.Sony VAIO VGN-SR190EBJ Battery

In 2007, the People's Republic of China was the largest producer of tin, where the tin deposits are concentrated in the southeast Yunnan tin belt, with 43% of the world's share, followed byIndonesia, with an almost equal share, and Peru at a distant third, reports the USGS.Sony VAIO VGN-SR190EBQ Battery

The table below shows the countries with the largest mine production and the largest smelter output.

After the discovery of tin in what is now Bisie, North Kivu in the Democratic Republic of the Congo in 2002, illegal production has increased there to around 15,000 tons. This is largely fueling the ongoing and recent conflicts there, as well as affecting international markets.Sony VAIO VGN-SR190EEJ/C Battery

Industry

The ten largest companies produced most of world's tin in 2007. It is not clear which of these companies include tin smelted from the mine at Bisie, Democratic Republic of the Congo, which is controlled by a renegade militia and produces 15,000 tons. Most of the world's tin is traded on the London Metal Exchange (LME), from 8 countries, under 17 brands.Sony VAIO VGN-SR190NAB Battery

Prices of tin were at US$11,900 per ton as of Nov 24, 2008. Prices reached an all-time high of nearly $25,000 per ton in May 2008, largely because of the effect of the decrease of tin production from Indonesia.

Exchanges

  • Kuala Lumpur Tin Market (KLTM), contract market
  • Indonesia Tin Exchange (INATIN), the solely physical market for tin will formally launchs at January 12, 2012

In 2006, about half of tin produced was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze, and niche uses.Sony VAIO VGN-SR190NDB Battery

Solder

Tin has long been used as a solder in the form of an alloy with lead, tin accounting for 5 to 70% w/w. Tin forms a eutectic mixture with lead containing 63% tin and 37% lead. Such solders are primarily used for solders for joining pipes or electric circuits.Sony VAIO VGN-SR190NEB Battery

Since the European Union Waste Electrical and Electronic Equipment Directive (WEEED) and Restriction of Hazardous Substances Directive (RoHS) came into effect on 1 July 2006, the use of lead in such alloys has decreased. Replacing lead has many problems, including a higher melting point, and the formation of tin whiskers causing electrical problems. Replacement alloys are rapidly being found, however.Sony VAIO VGN-SR190NGB Battery

Tin plating

Tin bonds readily to iron and is used for coating lead or zinc and steel to prevent corrosion. Tin-plated steel containers are widely used for food preservation, and this forms a large part of the market for metallic tin. A tinplate canister for preserving food was first manufactured in London in 1812.Sony VAIO VGN-SR190PAB Battery

Speakers of British English call them "tins", while speakers of American English call them "cans" or "tin cans". One thus-derived use of the slang term "tinnie" or "tinny" means "can of beer". The tin whistle is so called because it was first mass-produced in tin-plated steel.Sony VAIO VGN-SR190PCB Battery

Specialized alloys

Tin in combination with other elements forms a wide variety of useful alloys. Tin is most commonly alloyed with copper. Pewter is 85–99% tin; Babbitt metal has a high percentage of tin as well. Bronze is mostly copper (12% tin), while addition of phosphorus givesphosphor bronze. Bell metal is also a copper-tin alloy, containing 22% tin.Sony VAIO VGN-SR190PFB Battery

Tin has also sometimes been used in coinage; for example, it once formed a single figure percentage of the American and Canadian pennies. Because copper is often the major metal in such coins, and zinc is sometimes present as well, these could technically be called bronze and/or brass alloys.Sony VAIO VGN-SR19VN Battery

The niobium-tin compound Nb3Sn is commercially used as wires for superconducting magnets, due to the material's high critical temperature (18 K) and critical magnetic field (25 T). A superconducting magnet weighing only a couple of kilograms is capable of producing magnetic fields comparable to a conventional electromagnet weighing tons.Sony VAIO VGN-SR19VN Battery

A addition of a few percent tin is commonly used in zirconium alloys for the cladding of nuclear fuel.

Most metal pipes in a pipe organ are made of varying amounts of a tin/lead alloy, with 50%/50% being the most common. The amount of tin in the pipe defines the pipe's tone, since tin is the most tonally resonant of all metals.Sony VAIO VGN-SR19VRN Battery

When a tin/lead alloy cools, the lead cools slightly faster and produces a mottled or spotted effect. This metal alloy is referred to as spotted metal.

Other applications

Punched tin, also called pierced tin, is an artisan technique originating in central Europe for creating housewares that are both functional and decorative.Sony VAIO VGN-SR19XN Battery

Decorative piercing designs exist in a wide variety, based on geography or the artisan's personal creations. Punched tin lanterns are the most common application of this artisan technique. The light of a candle shining through the pierced design creates a decorative light pattern in the room where it sits.Sony VAIO VGN-SR19XN Battery

Punched tin lanterns and other punched tin articles were created in the New World from the earliest European settlement. A well-known example is the Revere type lantern, named after Paul Revere.

Before the modern era, in some areas of the Alps, a goat or sheep's horn would be sharpened and a tin panel would be punched out using the alphabet and numbers from one to nine.Sony VAIO VGN-SR210J/S Battery

This learning tool was known appropriately as "the horn". Modern reproductions are decorated with such motifs as hearts and tulips.

In America, pie safes and food safes came into use in the days before refrigeration. These were wooden cupboards of various styles and sizes - either floor standing or hanging cupboards meant to discourage vermin and insects and to keep dust from perishable foodstuffs.Sony VAIO VGN-SR21M/S Battery

These cabinets had tinplate inserts in the doors and sometimes in the sides, punched out by the homeowner, cabinetmaker or a tinsmith in varying designs to allow for air circulation. Modern reproductions of these articles remain popular in North America.

Window glass is most often made by floating molten glass on top of molten tin (creating float glass) in order to produce a flat surface. This is called the "Pilkington process".Sony VAIO VGN-SR21RM/H Battery

Tin(II) fluoride is added to some dental care products as stannous fluoride (SnF2). Tin(II) fluoride can be mixed with calcium abrasives while the more common sodium fluoride gradually becomes biologically inactive combined with calcium compounds. It has also been shown to be more effective than sodium fluoride in controlling gingivitis.Sony VAIO VGN-SR21RM/S Battery

Organotin compounds

Of all the chemical compounds of tin, the organotin compounds are most heavily used. Worldwide industrial production probably exceeds 50,000 tonnes.

PVC stabilizers

The major commercial application of organotin compounds is in the stabilization of PVC plastics.Sony VAIO VGN-SR220J/B Battery

In the absence of such stabilizers, PVC would otherwise rapidly degrade under heat, light, and atmospheric oxygen, to give discolored, brittle products. Tin scavenges labile chloride ions (Cl-), which would otherwise initiate loss of HCl from the plastic material.Sony VAIO VGN-SR220J/H Battery

Typical tin compounds are carboxylic acid derivatives of dibutyltin dichloride, such as the dilaurate.

Biocides

Organotin compounds can have a relatively high toxicity, which is both advantageous and problematic. They have been used for their biocidal effects in/as fungicides,pesticides, algaecides, wood preservatives, and antifouling agents.Sony VAIO VGN-SR240J/B Battery

Tributyltin oxide is used as a wood preservative.Tributyltin was used as additive for ship paint to prevent growth of marine organisms on ships, with use declining after organotin compounds were recognized as persistent organic pollutants with an extremely high toxicity for some marine organisms, for example the dog whelk.Sony VAIO VGN-SR240N/B Battery

The EU banned the use of organotin compounds in 2003, while concerns over the toxicity of these compounds to marine life and their effects on the reproduction and growth of some marine species, some reports describe biological effects to marine life at a concentration of 1 nanogram per liter) have led to a worldwide ban by the International Maritime Organization.Sony VAIO VGN-SR290JTH Battery

Many nations now restrict the use of organotin compounds to vessels over 25 meters long.

Organic chemistry

Some tin reagents are useful in organic chemistry. In the largest application, stannous chloride is a common reducing agent for the conversion of nitro and oximegroups to amines. The Stille reaction couples organotin compounds with organic halides or pseudohalides.Sony VAIO VGN-SR290JTJ Battery

Antimony is a toxic chemical element with the symbol Sb and an atomic number of 51. A lustrous grey metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Although the use of antimony is limited by its toxicity, its compounds have been of fundamental value in chemistry – a prominent example being the development of superacids derived from antimony pentafluoride.Sony VAIO VGN-SR290JTQ Battery

Antimony compounds are prominent fire retardantsfound in many commercial and domestic products. Certain alloys are valuable for use in solders and ball bearings. An emerging application is the use of antimony in microelectronics.

Antimony's sulfide compound, antimony(III) sulfide, Sb2S3 was recognized in antiquity, at least as early as3000 BC.Sony VAIO VGN-SR290JVB/C Battery

An artifact, said to be part of a vase, made of antimony dating to about 3000 BC was found at Tello,Chaldea (part of present-day Iraq), and a copper object plated with antimony dating between 2500 BC and 2200 BC has been found in Egypt.Sony VAIO VGN-SR290JVH/C Battery

One contemporary (Austen, at a lecture by Herbert Gladstone, published in 1892) was reported  to comment that "we only know of antimony at the present day as a highly brittle and crystalline metal, which could hardly be fashioned into a useful vase, and therefore this remarkable 'find' must represent the lost art of rendering antimony malleable."Sony VAIO VGN-SR290NTB Battery

However, Moorey was unconvinced that the artefact was indeed a vase, mentioning that Selimkhanov, after his analysis of the Telloh object (published in 1975), "attempted to relate the metal to Transcaucasian natural antimony" (i.e. native metal) and that "the antimony objects from Transcaucasia are all small personal ornaments."Sony VAIO VGN-SR29VN/S Battery

This weakens the evidence for a lost art "of rendering antimony malleable."

The first European description of a procedure for isolating antimony is in the book De la pirotechnia of 1540 by Vannoccio Biringuccio. This book predates the more famous 1556 book by Agricola, De re metallica, even though Agricola has been often incorrectly credited with the discovery of metallic antimony.Sony VAIO VGN-SR29XN/S Battery

A text describing the preparation of metallic antimony that was published in Germany in 1604 purported to date from the early fifteenth century, and if authentic it would predate Biringuccio. The book, written in Latin, was called "Currus Triumphalis Antimonii" (The Triumphal Chariot of Antimony), and its putative author was a certain Benedictine monk, writing under the name Basilius Valentinus.Sony VAIO VGN-SR2RVN/S Battery

An English translation of the "Currus Triumphalis" appeared in English in 1660, under the title The Triumphant Chariot of Antimony. The work remains of great interest, chiefly because it documents how followers of the renegade German physician, Philippus TheophrastusParacelsus von Hohenheim (of whom Thölde was one), came to associate the practice of alchemy with the preparation of chemical medicines.Sony VAIO VGN-SR390NAB Battery

Pure antimony was well known to J?bir ibn Hayy?n, sometimes called "the Father of Chemistry", in the 8th century. Here there is still an open controversy: Marcellin Berthelot, who translated a number of J?bir's books, stated that antimony is never mentioned in them,Sony VAIO VGN-SR390NAH Battery

but other authors  claim that Berthelot translated only some of the less important books, while the more interesting ones (some of which might describe antimony) are not yet translated, and their content is completely unknown.

The first natural occurrence of pure antimony ('native antimony') in the Earth's crust was described by the Swedish scientist and local mine district engineer Anton von Swab in 1783.Sony VAIO VGN-SR41M/P Battery

The type-sample was collected from the Sala Silver Mine in the Bergslagen mining district of Sala, Västmanland, Sweden.

Etymology

The ancient words for antimony mostly have, as their chief meaning, kohl, the sulfide of antimony. Pliny the Elder, however, distinguishes between male and female forms of antimony;Sony VAIO VGN-SR41M/S Battery

his male form is probably the sulfide, while the female form, which is superior, heavier, and less friable, is probably native metallic antimony.

The Egyptians called antimony m?dmt; in hieroglyphs, the vowels are uncertain, but there is an Arabic tradition that the word is ???????? mesdemet.Sony VAIO VGN-SR49VN/H Battery

The Greek word, ?????? stimmi, is probably a loan word from Arabic or Egyptian sdm

, and is used by the Attic tragic poets of the 5th century BC; later Greeks also used ????? stibi, as did Celsus andPliny, writing in Latin, in the first century AD. Pliny also gives the names stimi [sic], larbaris, alabaster, and the "very common" platyophthalmos, "wide-eye" (from the effect of the cosmetic).Sony VAIO VGN-SR51B/P Battery

Later Latin authors adapted the word to Latin asstibium. The Arabic word for the substance, as opposed to the cosmetic, can appear as ?????? ????? ?????? ????? ithmid, athmoud, othmod, or uthmod. Littré suggests the first form, which is the earliest, derives from stimmida, (one) accusative for stimmi.Sony VAIO VGN-SR51B/S Battery

The use of Sb as the standard chemical symbol for antimony is due to the 18th century chemical pioneer, Jöns Jakob Berzelius, who used this abbreviation of the name stibium.The medieval Latin form, from which the modern languages and lateByzantine Greek, take their names, is antimonium. Sony VAIO VGN-SR51MF Battery

The origin of this is uncertain; all suggestions have some difficulty either of form or interpretation. The popular etymology, from ??????????? anti-monachos or French antimoine, still has adherents; this would mean "monk-killer", and is explained by many early alchemists being monks, and antimony being poisonous.Sony VAIO VGN-SR51MF/P Battery

So does the hypothetical Greek word ????????? antimonos, "against one", explained as "not found as metal", or "not found unalloyed". Lippmann conjectured a Greek word, ?????????? anthemonion, which would mean "floret", and he cites several examples of related Greek words (but not that one) which describe chemical or biologicalefflorescence.Sony VAIO VGN-SR51MF/S Battery

The early uses of antimonium include the translations, in 1050–1100, by Constantine the African of Arabic medical treatises. Several authorities believe that antimonium is a scribal corruption of some Arabic form; Meyerhof derives it from ithmid;Sony VAIO VGN-SR51MF/W Battery

other possibilities include Athimar, the Arabic name of the metal, and a hypothetical as-stimmi, derived from or parallel to the Greek.

Characteristics

Antimony is in the nitrogen group (group 15) and has an electronegativity of 2.05. As expected by periodic trends, it is more electronegative than tin or bismuth, and less electronegative than tellurium or arsenic.Sony VAIO VGN-SR51MR Battery

Antimony is stable in air at room temperature but reacts with oxygen if heated to formantimony trioxide, Sb2O3.

Antimony is a silvery, lustrous gray metal that has a Mohs scale hardness of 3. Therefore, antimony by itself is not used to make hard objects: coins made of antimony were issued in China's Guizhou province in 1931, but because of their rapid wear their minting was discontinued.Antimony is resistant to attack by acids.Sony VAIO VGN-SR59VG Battery

Four allotropes of antimony are known: a stable metallic form, and three metastable forms: explosive, black and yellow. Metallic antimony is a brittle, silver-white shiny metal. When molten antimony is slowly cooled, metallic antimony crystallizes in an hexagonal cell,isomorphic with that of the grey allotrope of arsenic.Sony VAIO VGN-SR59VG/H Battery

A rare explosive form of antimony can be formed from the electrolysis of antimony(III) trichloride. When scratched with a sharp implement, an exothermic reaction occurs and white fumes given off as metallic antimony is formed; alternatively, when rubbed with a pestle in a mortar, a strong detonation occurs.Sony VAIO VGN-SR70B/S Battery

Black antimony is formed upon rapid cooling of gaseous metallic antimony. It has the same crystal structure as red phosphorus and black arsenic, it oxidizes in air and may ignite spontaneously. At 100 °C, it gradually transforms into the stable form. The yellow allotrope of antimony is the most unstable. It has only been generated by oxidation of stibine (SbH3) at ?90 °C.Sony VAIO VGN-SR72B/P Battery

Above this temperature and in ambient light, this meta stable allotrope transforms into the more stable black allotrope.

Metallic antimony adopts a double-layered structure (space group R3m No. 166) consisting of many interlocked ruffled six-membered rings.Sony VAIO VGN-SR72B/S Battery

Nearest and next-nearest neighbors form a distorted octahedral complex, with the three atoms in the same double-layer being slightly closer than the three atoms in the next. This relatively close packing leads to a high density of 6.697 g/cm3 whereas the low hardness and brittleness of antimony originate from the weak bonding among the layers.Sony VAIO VGN-SR73JB/S Battery

Antimony exists as two stable isotopes, 121Sb with a natural abundance of 57.36% and 123Sb with a natural abundance of 42.64%. It also has 35 radioisotopes, of which the longest-lived is 125Sb with a half-life of 2.75 years. In addition, 29 metastable states have been characterised.Sony VAIO VGN-SR74FB/S Battery

Occurrence

The abundance of antimony in the Earth's crust is estimated at 0.2 to 0.5 parts per million, comparable to thallium at 0.5 parts per million and silver at 0.07 ppm. Even though this element is not abundant, it is found in over 100 mineral species.Sony VAIO VGN-SR90FS Battery

Antimony is sometimes found native, but more frequently it is found in the sulfide stibnite (Sb2S3) which is the predominant ore mineral. Commercial forms of antimony are generally ingots, broken pieces, granules, and cast cake. Other forms are powder, shot, and single crystals.Sony VAIO VGN-SR90NS Battery

In 2005, the People's Republic of China was the top producer of antimony with about 84% world share followed at a distance by South Africa, Bolivia and Tajikistan, reports the British Geological Survey. The mine with the largest deposits in China is Xikuangshan Mine in Hunan province with a estimated deposit of 2.1 million metric tons.Sony VAIO VGN-SR90S Battery

In October 2011 a deposit of antimony was found in a shallow seabed about 50 km off Amami-Oshima Island in Kagoshima Prefecture. The discovery was the first time that antimony had been found at such shallow depths(480 meters), with this type of mineral deposit only ever having been found in depths in excess of 1000 meters.Sony VAIO VGN-SR90US Battery

Production

The extraction of antimony from ores depends on the quality of the ore, which is usually a sulfide. The sulfide is converted to an oxide and advantage is often taken of the volatility of antimony(III) oxide, which is recovered from roasting.Sony VAIO VGN-SR91NS Battery

This material is often used directly for the main applications, impurities being arsenic and sulfide. Antimony can be isolated from its ore by a reduction with scrap iron:

Sb2S3 + 3 Fe ? 2 Sb + 3 FeS

Isolating antimony from its oxide is performed by a carbothermal reduction:Sony VAIO VGN-SR91PS Battery

2 Sb2O3 + 3 C ? 4 Sb + 3 CO2

Compounds

Antimony compounds are often classified into those of Sb(III) and Sb(V).[26] Relative to its neighboring element As, the 5+ oxidaton state is more stable.

Oxides and hydroxides

Antimony trioxide (Sb4O6) is formed when antimony is burnt in air. In the gas phase, this compound exists as Sb4O6, but it polymerises upon condensing.Sony VAIO VGN-SR91S Battery

Antimony pentoxide, (Sb4O10) can only be formed by oxidation by concentrated nitric acid. Antimony also forms a mixed-valence oxide, antimony tetroxide (Sb2O4), which features both Sb(III) and Sb(V). Unlike phosphorus and arsenic, these various oxides are amphoteric and do not form well-defined oxoacids and react with acids to form antimony salts.Sony VAIO VGN-SR91US Battery

Antimonous acid Sb(OH)3 is unknown but the conjugate base sodium antimonite ([Na3SbO3]4) forms upon fusing sodium oxide and Sb4O6.[21]:763 Transition metal antimonites are also known.  Antimonic acid exists only as the hydrate HSb(OH)6, forming salts containing the antimonate anion Sb(OH)?6. Dehydrating metal salts containing this anion yields mixed oxides.Sony VAIO VGN-SR92NS Battery

Many antimony ores are sulfides, including stibnite (Sb2S3), pyrargyrite (Ag3SbS3), zinkenite, jamesonite, and boulangerite.[21]:757 Antimony pentasulfide is non-stoichiometric and features antimony in the +3 oxidation state and S-S bonds. Several thioantimonides are known such as [Sb6S10]2? and [Sb8S13]2?.Sony VAIO VGN-SR92PS Battery

Halides

Antimony forms two series of halides, SbX3 and SbX5. The trihalides SbF3, SbCl3, SbBr3, and SbI3 are all molecular compounds having trigonal pyramidal molecular geometry. The trifluoride SbF3 is prepared by the reaction of Sb2O3 with HF:Sony VAIO VGN-SR92S Battery

Sb2O3 + 6 HF ? 2 SbF3 + 3 H2O

It is Lewis acidic and readily accepts fluoride ions to form the complex anions SbF?
4 and SbF2?
5. Molten SbF3 is a weak electrical conductor. The trichloride SbCl3 is prepared by dissolving Sb2S3 in hydrochloric acid:Sony VAIO VGN-SR92US Battery

Sb2S3 + 6 HCl ? 2 SbCl3 + 3 H2S

The pentahalides SbF5 and SbCl5 have trigonal bipyramidal molecular geometry in the gas phase, but in the liquid phase, SbF5is polymeric, whereas SbCl5 is monomeric.[21]:761 SbF5 is a powerful Lewis acid used to make the superacid fluoroantimonic acid ("HSbF6").Sony VAIO VGN-SR93DS Battery

Oxyhalides are more common for antimony than arsenic and phosphorus. Antimony trioxide dissolves in concentrated acid to form antimony oxo- (antimonyl) compounds such as SbOCl and (SbO)2SO4.

Antimonides, hydrides, and organoantimony compounds

Compounds in this class generally are described as derivatives of Sb3-. Antimony forms antimonides with metals, such as indium antimonide(InSb), and silver antimonide (Ag3Sb).Sony VAIO VGN-SR93JS Batery

The alkali metal and zinc antimonides, e.g. Na3Sb and Zn3Sb2, are more reactive. Treating these antimonides with acid produces the unstable gas stibine, SbH3:

Sb3? + 3 H+ ? SbH3

Stibine can also be produced by treating Sb3+ salts with hydride reagents such as sodium borohydride. Stibine decomposes spontaneously at room temperature.Sony VAIO VGN-SR93PS Batttery

Because stibine is thermodynamically unstable (positive heat of formation), antimony does not react with hydrogen directly.

Organoantimony compounds are typically prepared by alkylation of antimony halides with Grignard reagents.A large variety of compounds are known with both Sb(III) and Sb(V) centers including mixed chloro-organic derivatives, anions, and cations.Sony VAIO VGN-SR93YS Battery

Examples include Sb(C6H5)3 (triphenylstibine), Sb2(C6H5)4 (with an Sb-Sb bond), and cyclic [Sb(C6H5)]n. Pentacoordinated organoantimony compounds are common, examples being Sb(C6H5)5 and several related halides.

Flame retardants

The main use of antimony is in the form of antimony trioxide is used in the making of flame-proofing compounds.Sony VAIO VGN-SR94FS Battery

Markets for these flame-retardant applications include children's clothing, toys, aircraft and automobile seat covers. It is also used in the fiberglass composites industry as an additive to polyester resins for such items as light aircraft engine covers. The resin will burn while a flame is held to it but will extinguish itself as soon as the flame is removed. Fireproofing consumes about half of the annual production of antimony.Sony VAIO VGN-SR94GS Battery

Alloys

Antimony forms a highly useful alloy with lead, increasing its hardness and mechanical strength. The Sb–Pb alloy is used in lead–acid batteries. It is used in antifriction alloys, such as Babbitt metal. It is used as an alloy in bullets and lead shot, cable sheathing, type metal (e.g. for linotype printing machines ), solder – some "lead-free" solders contain 5% Sb, in pewter, and in hardening alloys with low tin content in the manufacturing of organ pipes.Sony VAIO VGN-SR94HS Battery

Other applications

The second main application is as a catalyst for the production of the polymer polyethyleneterephthalate. It is an additive in some glasses. In the latter application, antimony oxides serve as fining agents, aiding in the removal of microscopic bubbles. This application is mainly used for TV screens.Sony VAIO VGN-SR94VS Battery

Microelectronics

In tiny amounts, antimony is increasingly being used in the semiconductor industry as a dopant for ultra-high conductivity n-type silicon wafers in the production of diodes, infrared detectors, and Hall-effect devices.

In the 1950s, tiny beads of a lead-antimony alloy were used to dope the emitters and collectors of NPN alloy junction transistors with antimony.Sony VAIO VGN-SZ35B/B Battery

Medical

Few biological or medical applications exist for antimony. Treatments principally containing antimony are known as antimonials and are used as emetics.

Antimony compounds are used as antiprotozoan drugs. Antimony potassium tartrate, or tartar emetic, was once used as an anti-schistosomal drug, subsequently replaced by praziquantel.Sony VAIO VGN-SZ54B/B Battery

Antimony and its compounds are used in several veterinary preparations like anthiomaline or lithium antimony thiomalate, which is used as a skin conditioner inruminants.

Antimony has a nourishing or conditioning effect on keratinized tissues, at least in animals.Sony VAIO VGN-SZ55B/B Battery

Antimony-based drugs, such as meglumine antimoniate, are also considered the drugs of choice for treatment of leishmaniasis in domestic animals. Unfortunately, as well as having low therapeutic indices, the drugs are poor at penetrating the bone marrow, where some of the Leishmania amastigotes reside, and so cure of the disease – especially the visceral form – is very difficult.Sony VAIO VGN-SZ55GN/B Battery

Elemental antimony as an antimony pill was once used as a medicine. It could be reused by others after ingestion.

Other uses

In the heads of some safety matches  and in nuclear reactors together with beryllium as startup neutron sources.

Antimony sulfides have been shown to help stabilize the friction coefficient in automotive brake pad materials.Sony VAIO VGN-SZ56 Battery

Antimony also is used in the making of bullets and bullet tracers. This element is also used in cosmetics and event paint and glass art crafts.

Precautions

Antimony and many of its compounds are toxic, and the effects of antimony poisoning are similar to arsenic poisoning. Inhalation of antimony dust is harmful and in certain cases may be fatal;Sony VAIO VGN-SZ561N Battery

in small doses, antimony causes headaches, dizziness, and depression. Larger doses such as prolonged skin contact may cause dermatitis; otherwise it can damage the kidneys and the liver, causing violent and frequent vomiting, and will lead to death in a few days.Sony VAIO VGN-SZ562N Battery

Antimony is incompatible with strong oxidizing agents, strong acids, halogen acids, chlorine, or fluorine. It should be kept away from heat.

Antimony leaches from polyethylene terephthalate (PET) bottles into liquids.  Sony VAIO VGN-SZ57N Battery

While levels observed for bottled water are below drinking water guidelines, fruit juice concentrates (for which no guidelines are established) produced in the UK were found to contain up to 44.7 µg/L of antimony, well above the EU limits fortap water of 5 µg/L.Sony VAIO VGN-SZ58GN Battery,Sony VAIO VGN-SZ58GN/C Battery,Sony VAIO VGN-SZ58N Battery,Sony VAIO VGN-SZ61MN/B Battery,Sony VAIO VGN-SZ61VN/X Battery

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