Reproducibility/naacl22_wikitext15M · Datasets at Hugging Face

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3 is prepared by the reaction of Sb
2O
3 with HF :
Sb
2O
3 + 6 HF → 2 SbF
3 + 3 H
2O
It is Lewis acidic and readily accepts fluoride ions to form the complex anions SbF −
4 and <unk> −
5 . Molten SbF
3 is a weak electrical conductor . The trichloride SbCl
3 is prepared by dissolving Sb
2S
3 in hydrochloric acid :
Sb
2S
3 + 6 HCl → 2 SbCl
3 + 3 H
2S
The pentahalides SbF
5 and SbCl
5 have trigonal bipyramidal molecular geometry in the gas phase , but in the liquid phase , SbF
5 is polymeric , whereas SbCl
5 is monomeric . SbF
5 is a powerful Lewis acid used to make the <unk> <unk> acid ( " <unk> " ) .
Oxyhalides are more common for antimony than arsenic and phosphorus . Antimony trioxide dissolves in concentrated acid to form <unk> compounds such as <unk> and ( SbO )
2SO
4 .

= = = <unk> , hydrides , and organoantimony compounds = = =

Compounds in this class generally are described as derivatives of Sb3 − . Antimony forms antimonides with metals , such as indium antimonide ( <unk> ) and silver antimonide ( Ag
<unk> ) . The alkali metal and zinc antimonides , such as <unk> and <unk> , are more reactive . Treating these antimonides with acid produces the unstable gas stibine , <unk>
3 :
Sb3 − + 3 H + → <unk>
3
<unk> can also be produced by treating Sb3 + salts with hydride reagents such as sodium <unk> decomposes spontaneously at room temperature . Because stibine has a positive heat of formation , it is thermodynamically unstable and thus antimony does not react with hydrogen directly .
<unk> 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 . Examples include Sb ( C6H5 ) 3 ( <unk> ) , Sb2 ( C6H5 ) 4 ( with an Sb @-@ Sb bond ) , and cyclic [ Sb ( C6H5 ) ] n . <unk> organoantimony compounds are common , examples being Sb ( C6H5 ) 5 and several related halides .

= = History = =

Antimony ( III ) sulfide , Sb2S3 , was recognized in predynastic Egypt as an eye cosmetic ( kohl ) as early as about 3100 BC , when the cosmetic palette was invented .
An artifact , said to be part of a vase , made of antimony dating to about 3000 BC was found at <unk> , 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 . Austen , at a lecture by Herbert Gladstone in 1892 commented 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 ' ( artifact mentioned above ) must represent the lost art of rendering antimony malleable . "
<unk> was unconvinced the artifact was indeed a vase , mentioning that <unk> , after his analysis of the Tello 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 . " This weakens the evidence for a lost art " of rendering antimony malleable . "
The Roman scholar Pliny the Elder described several ways of preparing antimony sulfide for medical purposes in his treatise Natural History . Pliny the Elder also made a distinction between " male " and " female " forms of antimony ; the male form is probably the sulfide , while the female form , which is superior , heavier , and less friable , has been suspected to be native metallic antimony .
The Roman naturalist Pedanius Dioscorides mentioned that antimony sulfide could be roasted by heating by a current of air . It is thought that this produced metallic antimony .
The first description of a procedure for isolating antimony is in the book De la <unk> of 1540 by Vannoccio Biringuccio ; this predates the more famous 1556 book by Agricola , De re metallica . In this context Agricola has been often incorrectly credited with the discovery of metallic antimony . The book <unk> <unk> <unk> ( The Triumphal Chariot of Antimony ) , describing the preparation of metallic antimony , was published in Germany in 1604 . It was purported to have been written by a Benedictine monk , writing under the name Basilius Valentinus , in the 15th century ; if it were authentic , which it is not , it would predate Biringuccio .
The metal antimony was known to German chemist Andreas Libavius in 1615 who obtained it by adding iron to a molten mixture of antimony sulfide , salt and potassium tartrate . This procedure produced antimony with a crystalline or starred surface .
With the advent of challenges to phlogiston theory it was recognized that antimony is an element forming sulfides , oxides , and other compounds , as is the case with other metals .
The first natural occurrence of pure antimony in the Earth 's crust was described by the Swedish scientist and local mine district engineer Anton von <unk> in 1783 ; the type @-@ sample was collected from the Sala Silver Mine in the <unk> mining district of Sala , <unk> , Sweden .

= = = Etymology = = =

The ancient words for antimony mostly have , as their chief meaning , kohl , the sulfide of antimony .
The Egyptians called antimony <unk> ; in hieroglyphs , the vowels are uncertain , but there is an Arabic tradition that the word is <unk> <unk> . The Greek word , <unk> stimmi , is probably a loan word from Arabic or from Egyptian <unk>
and is used by Attic tragic poets of the 5th century BC ; later Greeks also used <unk> <unk> , as did Celsus and Pliny , writing in Latin , in the first century AD . Pliny also gives the names <unk> [ sic ] , <unk> , alabaster , and the " very common " <unk> , " wide @-@ eye " ( from the effect of the cosmetic ) . Later Latin authors adapted the word to Latin as stibium . The Arabic word for the substance , as opposed to the cosmetic , can appear as <unk> <unk> , <unk> , <unk> , or <unk> . <unk> suggests the first form , which is the earliest , derives from <unk> , an accusative for stimmi .
The use of Sb as the standard chemical symbol for antimony is due to Jöns Jakob Berzelius , who used this abbreviation of the name stibium . The medieval Latin form , from which the modern languages and late Byzantine Greek take their names for antimony , is antimonium . The origin of this is uncertain ; all suggestions have some difficulty either of form or interpretation . The popular etymology , from <unk> anti @-@ <unk> or French <unk> , still has adherents ; this would mean " monk @-@ killer " , and is explained by many early alchemists being monks , and antimony being poisonous .
Another popular etymology is the hypothetical Greek word <unk> <unk> , " against aloneness " , explained as " not found as metal " , or " not found unalloyed " . Lippmann conjectured a hypothetical Greek word <unk> <unk> , which would mean " <unk> " , and cites several examples of related Greek words ( but not that one ) which describe chemical or biological efflorescence .
The early uses of antimonium include the translations , in 1050 – 1100 , by Constantine the African of Arabic medical treatises . Several authorities believe antimonium is a scribal corruption of some Arabic form ; <unk> derives it from <unk> ; other possibilities include <unk> , the Arabic name of the metalloid , and a hypothetical as @-@ stimmi , derived from or parallel to the Greek .

= = Production = =


= = = Top producers and production volumes = = =

The British Geological Survey ( BGS ) reported that in 2005 , China was the top producer of antimony with an approximately 84 % world share , followed at a distance by South Africa , Bolivia and Tajikistan . <unk> Mine in Hunan province has the largest deposits in China with an estimated deposit of 2 @.@ 1 million metric tons .
In 2010 , according to the US Geological Survey , China accounted for 88 @.@ 9 % of total antimony production with South Africa , Bolivia and Russia sharing the second place .
However , Roskill Consulting estimates for primary production show that in 2010 China held a 76 @.@ 75 % share of world supply with 120 @,@ 462 tonnes ( 90 @,@ 000 tonnes of reported and 30 @,@ 464 tonnes of un @-@ reported production ) , followed by Russia ( 4 @.@ 14 % share , 6 @,@ 500 tonnes of production ) , Myanmar ( 3 @.@ 76 % share , 5 @,@ 897 tonnes ) , Canada ( 3 @.@ 61 % share , 5 @,@ 660 tonnes ) , Tajikistan ( 3 @.@ 42 % share , 5 @,@ 370 tonnes ) and Bolivia ( 3 @.@ 17 % share , 4 @,@ 980 tonnes ) .
Roskill estimates that secondary production globally in 2010 was 39 @,@ 540 tonnes .
Antimony was ranked first in a Risk List published by the British Geological Survey in the second half of 2011 . The list provides an indication of the relative risk to the supply of chemical elements or element groups required to maintain the current British economy and lifestyle .
Also , antimony was identified as one of 12 critical raw materials for the EU in a report published in 2011 , primarily due to the lack of supply outside China .
Reported production of antimony in China fell in 2010 and is unlikely to increase in the coming years , according to the Roskill report . No significant antimony deposits in China have been developed for about ten years , and the remaining economic reserves are being rapidly depleted .
The world 's largest antimony producers , according to Roskill , are listed below :

= = = Reserves = = =

According to statistics from the USGS , current global reserves of antimony will be depleted in 13 years . However , the USGS expects more resources will be found .

= = = Production process = = =

The extraction of antimony from ores depends on the quality of the ore and composition of the ore . Most antimony is mined as the sulfide ; lower @-@ grade ores are concentrated by froth flotation , while higher @-@ grade ores are heated to 500 – 600 ° C , the temperature at which stibnite melts and is separated from the gangue minerals . Antimony can be isolated from the crude antimony sulfide by a reduction with scrap iron :
Sb
2S
3 + 3 Fe → 2 Sb + 3 FeS
The sulfide is converted to an oxide and advantage is often taken of the volatility of antimony ( III ) oxide , which is recovered from roasting . This material is often used directly for the main applications , impurities being arsenic and sulfide . Isolating antimony from its oxide is performed by a carbothermal reduction :
2 Sb
2O
3 + 3 C → 4 Sb + 3 CO
2
The lower @-@ grade ores are reduced in blast furnaces while the higher @-@ grade ores are reduced in reverberatory furnaces .

= = Applications = =

About 60 % of antimony is consumed in flame retardants , and 20 % is used in alloys for batteries , plain bearings and solders .

= = = Flame retardants = = =

Antimony is mainly used as its trioxide in making flame @-@ proofing compounds . It is nearly always used in combination with halogenated flame retardants , with the only exception being in halogen @-@ containing polymers . The formation of halogenated antimony compounds is the cause for the flame retarding effect of antimony trioxide , due to reaction of these compounds with hydrogen atoms and probably also with oxygen atoms and OH radicals , thus inhibiting fire . 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 .

3 is prepared by the reaction of Sb

2O

3 with HF :

Sb

2O

3 + 6 HF → 2 SbF

3 + 3 H

2O

It is Lewis acidic and readily accepts fluoride ions to form the complex anions SbF −

4 and <unk> −

5 . Molten SbF

3 is a weak electrical conductor . The trichloride SbCl

3 is prepared by dissolving Sb

2S

3 in hydrochloric acid :

Sb

2S

3 + 6 HCl → 2 SbCl

3 + 3 H

2S

The pentahalides SbF

5 and SbCl

5 have trigonal bipyramidal molecular geometry in the gas phase , but in the liquid phase , SbF

5 is polymeric , whereas SbCl

5 is monomeric . SbF

5 is a powerful Lewis acid used to make the <unk> <unk> acid ( " <unk> " ) .

Oxyhalides are more common for antimony than arsenic and phosphorus . Antimony trioxide dissolves in concentrated acid to form <unk> compounds such as <unk> and ( SbO )

2SO

4 .

= = = <unk> , hydrides , and organoantimony compounds = = =

Compounds in this class generally are described as derivatives of Sb3 − . Antimony forms antimonides with metals , such as indium antimonide ( <unk> ) and silver antimonide ( Ag

<unk> ) . The alkali metal and zinc antimonides , such as <unk> and <unk> , are more reactive . Treating these antimonides with acid produces the unstable gas stibine , <unk>

3 :

Sb3 − + 3 H + → <unk>

3

<unk> can also be produced by treating Sb3 + salts with hydride reagents such as sodium <unk> decomposes spontaneously at room temperature . Because stibine has a positive heat of formation , it is thermodynamically unstable and thus antimony does not react with hydrogen directly .

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

= = History = =

Antimony ( III ) sulfide , Sb2S3 , was recognized in predynastic Egypt as an eye cosmetic ( kohl ) as early as about 3100 BC , when the cosmetic palette was invented .

An artifact , said to be part of a vase , made of antimony dating to about 3000 BC was found at <unk> , 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 . Austen , at a lecture by Herbert Gladstone in 1892 commented 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 ' ( artifact mentioned above ) must represent the lost art of rendering antimony malleable . "

<unk> was unconvinced the artifact was indeed a vase , mentioning that <unk> , after his analysis of the Tello 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 . " This weakens the evidence for a lost art " of rendering antimony malleable . "

The Roman scholar Pliny the Elder described several ways of preparing antimony sulfide for medical purposes in his treatise Natural History . Pliny the Elder also made a distinction between " male " and " female " forms of antimony ; the male form is probably the sulfide , while the female form , which is superior , heavier , and less friable , has been suspected to be native metallic antimony .

The Roman naturalist Pedanius Dioscorides mentioned that antimony sulfide could be roasted by heating by a current of air . It is thought that this produced metallic antimony .

The first description of a procedure for isolating antimony is in the book De la <unk> of 1540 by Vannoccio Biringuccio ; this predates the more famous 1556 book by Agricola , De re metallica . In this context Agricola has been often incorrectly credited with the discovery of metallic antimony . The book <unk> <unk> <unk> ( The Triumphal Chariot of Antimony ) , describing the preparation of metallic antimony , was published in Germany in 1604 . It was purported to have been written by a Benedictine monk , writing under the name Basilius Valentinus , in the 15th century ; if it were authentic , which it is not , it would predate Biringuccio .

The metal antimony was known to German chemist Andreas Libavius in 1615 who obtained it by adding iron to a molten mixture of antimony sulfide , salt and potassium tartrate . This procedure produced antimony with a crystalline or starred surface .

With the advent of challenges to phlogiston theory it was recognized that antimony is an element forming sulfides , oxides , and other compounds , as is the case with other metals .

The first natural occurrence of pure antimony in the Earth 's crust was described by the Swedish scientist and local mine district engineer Anton von <unk> in 1783 ; the type @-@ sample was collected from the Sala Silver Mine in the <unk> mining district of Sala , <unk> , Sweden .

= = = Etymology = = =

The ancient words for antimony mostly have , as their chief meaning , kohl , the sulfide of antimony .

The Egyptians called antimony <unk> ; in hieroglyphs , the vowels are uncertain , but there is an Arabic tradition that the word is <unk> <unk> . The Greek word , <unk> stimmi , is probably a loan word from Arabic or from Egyptian <unk>

and is used by Attic tragic poets of the 5th century BC ; later Greeks also used <unk> <unk> , as did Celsus and Pliny , writing in Latin , in the first century AD . Pliny also gives the names <unk> [ sic ] , <unk> , alabaster , and the " very common " <unk> , " wide @-@ eye " ( from the effect of the cosmetic ) . Later Latin authors adapted the word to Latin as stibium . The Arabic word for the substance , as opposed to the cosmetic , can appear as <unk> <unk> , <unk> , <unk> , or <unk> . <unk> suggests the first form , which is the earliest , derives from <unk> , an accusative for stimmi .

The use of Sb as the standard chemical symbol for antimony is due to Jöns Jakob Berzelius , who used this abbreviation of the name stibium . The medieval Latin form , from which the modern languages and late Byzantine Greek take their names for antimony , is antimonium . The origin of this is uncertain ; all suggestions have some difficulty either of form or interpretation . The popular etymology , from <unk> anti @-@ <unk> or French <unk> , still has adherents ; this would mean " monk @-@ killer " , and is explained by many early alchemists being monks , and antimony being poisonous .

Another popular etymology is the hypothetical Greek word <unk> <unk> , " against aloneness " , explained as " not found as metal " , or " not found unalloyed " . Lippmann conjectured a hypothetical Greek word <unk> <unk> , which would mean " <unk> " , and cites several examples of related Greek words ( but not that one ) which describe chemical or biological efflorescence .

The early uses of antimonium include the translations , in 1050 – 1100 , by Constantine the African of Arabic medical treatises . Several authorities believe antimonium is a scribal corruption of some Arabic form ; <unk> derives it from <unk> ; other possibilities include <unk> , the Arabic name of the metalloid , and a hypothetical as @-@ stimmi , derived from or parallel to the Greek .

= = Production = =

= = = Top producers and production volumes = = =

The British Geological Survey ( BGS ) reported that in 2005 , China was the top producer of antimony with an approximately 84 % world share , followed at a distance by South Africa , Bolivia and Tajikistan . <unk> Mine in Hunan province has the largest deposits in China with an estimated deposit of 2 @.@ 1 million metric tons .

In 2010 , according to the US Geological Survey , China accounted for 88 @.@ 9 % of total antimony production with South Africa , Bolivia and Russia sharing the second place .

However , Roskill Consulting estimates for primary production show that in 2010 China held a 76 @.@ 75 % share of world supply with 120 @,@ 462 tonnes ( 90 @,@ 000 tonnes of reported and 30 @,@ 464 tonnes of un @-@ reported production ) , followed by Russia ( 4 @.@ 14 % share , 6 @,@ 500 tonnes of production ) , Myanmar ( 3 @.@ 76 % share , 5 @,@ 897 tonnes ) , Canada ( 3 @.@ 61 % share , 5 @,@ 660 tonnes ) , Tajikistan ( 3 @.@ 42 % share , 5 @,@ 370 tonnes ) and Bolivia ( 3 @.@ 17 % share , 4 @,@ 980 tonnes ) .

Roskill estimates that secondary production globally in 2010 was 39 @,@ 540 tonnes .

Antimony was ranked first in a Risk List published by the British Geological Survey in the second half of 2011 . The list provides an indication of the relative risk to the supply of chemical elements or element groups required to maintain the current British economy and lifestyle .

Also , antimony was identified as one of 12 critical raw materials for the EU in a report published in 2011 , primarily due to the lack of supply outside China .

Reported production of antimony in China fell in 2010 and is unlikely to increase in the coming years , according to the Roskill report . No significant antimony deposits in China have been developed for about ten years , and the remaining economic reserves are being rapidly depleted .

The world 's largest antimony producers , according to Roskill , are listed below :

= = = Reserves = = =

According to statistics from the USGS , current global reserves of antimony will be depleted in 13 years . However , the USGS expects more resources will be found .

= = = Production process = = =

The extraction of antimony from ores depends on the quality of the ore and composition of the ore . Most antimony is mined as the sulfide ; lower @-@ grade ores are concentrated by froth flotation , while higher @-@ grade ores are heated to 500 – 600 ° C , the temperature at which stibnite melts and is separated from the gangue minerals . Antimony can be isolated from the crude antimony sulfide by a reduction with scrap iron :

Sb

2S

3 + 3 Fe → 2 Sb + 3 FeS

The sulfide is converted to an oxide and advantage is often taken of the volatility of antimony ( III ) oxide , which is recovered from roasting . This material is often used directly for the main applications , impurities being arsenic and sulfide . Isolating antimony from its oxide is performed by a carbothermal reduction :

2 Sb

2O

3 + 3 C → 4 Sb + 3 CO

2

The lower @-@ grade ores are reduced in blast furnaces while the higher @-@ grade ores are reduced in reverberatory furnaces .

= = Applications = =

About 60 % of antimony is consumed in flame retardants , and 20 % is used in alloys for batteries , plain bearings and solders .

= = = Flame retardants = = =

Antimony is mainly used as its trioxide in making flame @-@ proofing compounds . It is nearly always used in combination with halogenated flame retardants , with the only exception being in halogen @-@ containing polymers . The formation of halogenated antimony compounds is the cause for the flame retarding effect of antimony trioxide , due to reaction of these compounds with hydrogen atoms and probably also with oxygen atoms and OH radicals , thus inhibiting fire . 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 .