الفا (α-S8): 2.07 گرام في ڪعبي سينٽي ميٽر بيٽا (β-S8): 1.96 گرام في ڪعبي سينٽي ميٽر گاما (γ-S8): 1.92 گرام في ڪعبي سينٽي ميٽر
حالت (STP تي)
ٺوس
حڪومتطبيعي خاصيتون
•قسم
غير ڌات
•پگھلڻ جو نقطو
الفا (α-S8): 388.36°K (115.21°C)
•پگھرائڻ لاء حرارت
بيٽا (β-S8): 1.727 ڪلو جول في مول
•ٻاڦ جي حرارت
بيٽا (β-S8): 1.727 ڪلو جول في مول
•مولر گرميء گنجائش
22.75 جول في مول.ڪيلون
گندرف (Sulphur) ھڪڪيميائي عنصر آھي. ھن جو نشان "S" ۽ ايٽمي نمبر "16" آھي. اهو گهڻو (abundant)، ملٽي ويلنٽ ۽ غير ڌاتو آهي. عام حالتن ۾، گندرف جا ايٽم ڪيميائي فارمولا S8 سان چڪري آڪٽا ائٽامڪ (cyclicoctoatomic) ماليڪيول ٺاهيندا آهن. عنصري گندرف ڪمري جي حرارت تي هڪ روشن پيلو ۽ ڪرسٽل وارو ٺوس آهي.
گندرف ڪائنات ۾ وزن جي لحاظ کان ڏهين نمبر تي سڀ کان وڌيڪ ۽ زمين تي پنجين نمبر تي سڀ کان وڌيڪ عام عنصر آهي. جيتوڻيڪ ڪڏهن ڪڏهن خالص، اصلي شڪل ۾ ملي ٿو، پر زمين تي گندرف عام طور تي سلفائيڊ ۽ سلفيٽ معدنيات طور ملي ٿو. اصلي شڪل ۾ وافر هجڻ ڪري، سلفر قديم زماني ۾ سڃاتو ويندو هو، قديم هندستان، يونان، چين ۽ مصر ۾ ان جي استعمال لاءِ ذڪر ڪيو ويندو هو. تاريخي طور تي سلفر کي برم اسٽون (brimestone) به سڏيو ويندو آهي، جنهن جو مطلب آهي "جلندڙ پٿر". تقريبن سڀئي عنصري سلفر قدرتي گئس ۽ پيٽروليم مان سلفر تي مشتمل آلودگي کي هٽائڻ جي ضمني پيداوار جي طور تي پيدا ڪيا ويندا آهن. عنصر جو سڀ کان وڏو تجارتي استعمال سلفيٽ ۽ فاسفيٽ ڀاڻ ۽ ٻين ڪيميائي عملن لاءِ سلفرڪ ايسڊ جي پيداوار آهي. سلفر کي ماچس، حشرات مار دوائن ۽ فنگسائيڊ ۾ استعمال ڪيو ويندو آهي. ڪيترائي سلفر مرڪب بدبودار آهن ۽ قدرتي گئس، اسڪنڪ بدبوءِ، انگور ۽ لہسن جي بوءِ آرگنو سلفر مرڪب جي ڪري آهي. هائيڊروجن سلفائيڊ سڙيل انڊن ۽ ٻين حياتياتي عملن کي خاصيت واري بو ڏئي ٿو.
سلفر سڀني زندگين لاءِ هڪ ضروري عنصر آهي، تقريبن هميشه آرگنو سلفر مرڪب يا ڌاتو سلفائيڊ جي صورت ۾. امينو ايسڊ (ٻه پروٽينوجينڪ: سيسٽين ۽ ميٿيونين، ۽ ٻيا ڪيترائي غير ڪوڊ ٿيل: سيسٽين، تورين، وغيره) ۽ ٻه وٽامن (بايوٽين ۽ ٿاامين) زندگي لاءِ اهم آرگنوسلفر مرڪب آهن. ڪيترن ئي ڪوفيڪٽرز ۾ سلفر پڻ شامل آهي، جنهن ۾ گلوٽاٿيون، ۽ آئرن-سلفر پروٽين شامل آهن. ڊِسلفائيڊس، ايس-ايس بانڊ، ٻاهرين چمڙي ۽ وارن ۾ موجود (ٻين جي وچ ۾) پروٽين ڪيريٽين جي ميڪانياتي طاقت ۽ حل نه ٿيڻ جي صلاحيت ڏين ٿا.
سلفر ڪيترائي پولي ايٽامڪ ماليڪيول ٺاهيندو آهي. سڀ کان وڌيڪ مشهور ايلوٽروپ آڪٽاسلفر، سائڪلو-S8 آهي. سائڪلو-S8 جو پوائنٽ گروپ D4d آهي ۽ ان جو ڊائپول لمحو 0 - D آهي.[1] آڪٽاسلفر هڪ نرم، روشن پيلو ٺوس آهي جيڪو بدبودار آهي. اهو (115.21°C) (239.38 °F) تي ڳري ٿو، ۽ (444.6°C) (832.3 °F) تي اُبلندو آهي. (95.2°C) (203.4 °F) تي، ان جي پگھلڻ واري درجه حرارت کان هيٺ، سائڪلو-آڪٽاسلفر آهستي آهستي α- آڪٽاسلفر کان β-پوليمورف ۾ تبديل ٿيڻ شروع ڪري ٿو. S8 رنگ جي جوڙجڪ هن مرحلي جي منتقلي سان عملي طور تي تبديل نه ٿيندي آهي، جيڪا بين-ماليڪيولر رابطي کي متاثر ڪري ٿي. پگھريل سلفر کي ٿڌو ڪرڻ سان (119.6°C) (247.3 °F) تي جمي ويندو آهي،[2] ڇاڪاڻ ته اهو گهڻو ڪري β-S8 ماليڪيولن تي مشتمل هوندو آهي. پنهنجي پگھلڻ ۽ اُبلندڙ گرمي پد جي وچ ۾، آڪٽاسلفر پنهنجي ايلوٽروپ کي ٻيهر تبديل ڪري ٿو، β-آڪٽاسلفر کان γ-سلفر ڏانهن رخ ڪري ٿو، ٻيهر گهٽ کثافت سان گڏ پر پوليمر جي ٺهڻ جي ڪري ويسڪوسيٽي وڌي ٿي. وڌيڪ گرمي پد تي، ڊيپوليمرائيزيشن ٿيڻ سان ويسڪوسيٽي گهٽجي ويندي آهي. پگھريل سلفر 200 °C (392 °F) کان مٿي هڪ ڳاڙهو ڳاڙهو رنگ اختيار ڪري ٿو. سلفر جي کثافت تقريباً 2 g/cm3 آهي، جيڪو ايلوٽروپ تي منحصر آهي؛ سڀئي مستحڪم ايلوٽروپ بهترين برقي انسولٽر آهن.
سلفر 20 °C (68 °F) ۽ 50 °C (122 °F) جي وچ ۾ تصعید جو عمل (حالت کي سڌو سنئون ٺوس کان بخارات (گيس) ۾ تبديل ڪرڻ) (sublimation) ڪندو آهي.[3] سلفر پاڻيءَ ۾ حل نه ٿيندڙ آهي پر ڪاربان ڊائي سلفائيڊ (CS2) ۽ گهٽ حد تائين، ٻين غير قطبي نامياتي محلولن ۾، جهڙوڪ بينزين ۽ ٽولوئين، ۾ حل ٿيندڙ آهي.
Left: Liquid hydrogen sulfide inside a test tube. Right: A bottle of sulfuric acid.
The reaction involves adsorption of protons ontoسانچو:Chem clusters, followed bydisproportionation into the reaction products.[4]
The second, fourth and sixthionization energies of sulfur are 2252kJ/mol, 4556kJ/mol and 8495.8kJ/mol, respectively. The composition of reaction products of sulfur with oxidants (and its oxidation state) depends on whether releasing of reaction energy overcomes these thresholds. Applyingcatalysts and/orsupply of external energy may vary sulfur's oxidation state and the composition of reaction products. While reaction between sulfur and oxygen under normal conditions gives sulfur dioxide (oxidation state +4), formation ofsulfur trioxide (oxidation state +6) requires a temperature of400–600°C (750–1٬100°F) and presence of a catalyst.
In reactions with elements of lesserelectronegativity, it reacts as an oxidant and forms sulfides, where it has oxidation state −2.
Sulfur reacts with nearly all other elements except noble gases, even with the notoriously unreactive metaliridium (yieldingiridium disulfide).[5] Some of those reactions require elevated temperatures.[6]
Sulfur forms over 30 solidallotropes, more than any other element.[7] Besides S8, several other rings are known.[8] Removing one atom from the crown gives S7, which is of a deeper yellow than S8.HPLC analysis of "elemental sulfur" reveals an equilibrium mixture of mainly S8, but with S7 and small amounts of S6.[9] Larger rings have been prepared, including S12 and S18.[10][11]
Amorphous or "plastic" sulfur is produced by rapid cooling of molten sulfur—for example, by pouring it into cold water.X-ray crystallography studies show that the amorphous form may have ahelical structure with eight atoms per turn. The long coiled polymeric molecules make the brownish substanceelastic, and in bulk it has the feel of crude rubber. This form ismetastable at room temperature and gradually reverts to the crystalline molecular allotrope, which is no longer elastic. This process happens over a matter of hours to days, but can be rapidly catalyzed.سانچو:Clear left
Sulfur has 23 knownisotopes, four of which are stable:32S (94.99±0.26%),33S (0.75±0.02%),34S (4.25±0.24%), and36S (0.01±0.01%). Other than35S, with ahalf-life of 87 days, theradioactive isotopes of sulfur have half-lives less than 3hours.
The preponderance of32S is explained by its production in the so-called alpha-process (one of the main classes of nuclear fusion reactions) in exploding stars. Other stable sulfur isotopes are produced in the bypass processes related with34Ar, and their composition depends on a type of a stellar explosion. For example, proportionally more33S comes fromnovae than fromsupernovae.[12]
On the planet Earth the sulfur isotopic composition was determined by the Sun. Though it was assumed that the distribution of different sulfur isotopes would be more or less equal, it has been found that proportions of the two most abundant sulfur isotopes32S and34S varies in different samples. Assaying of the isotope ratio (δ34S) in the samples suggests their chemical history, and with support of other methods, it allows to age-date the samples, estimate temperature of equilibrium between ore and water, determine pH and oxygenfugacity, identify the activity of sulfate-reducing bacteria in the time of formation of the sample, or suggest the main sources of sulfur in ecosystems.[13] However, there are ongoing discussions over the real reason for the δ34S shifts, biological activity or postdeposit alteration.[14]
For example, whensulfide minerals are precipitated, isotopic equilibration among solids and liquid may cause small differences in the δ34S values of co-genetic minerals. The differences between minerals can be used to estimate the temperature of equilibration. Theδ13C and δ34S of coexistingcarbonate minerals and sulfides can be used to determine thepH and oxygen fugacity of the ore-bearing fluid during ore formation.
Scientists measure thesulfur isotopes ofminerals in rocks andsediments to study theredox conditions in past oceans.Sulfate-reducing bacteria in marine sediment fractionatesulfur isotopes as they take insulfate and producesulfide. Prior to the 2010s, it was thought that sulfate reduction could fractionatesulfur isotopes up to 46permil[15] and fractionation larger than 46 permil recorded in sediments must be due todisproportionation of sulfur compounds in the sediment. This view has changed since the 2010s as experiments showed thatsulfate-reducing bacteria can fractionate to 66 permil.[16] As substrates for disproportionation are limited by the product ofsulfate reduction, the isotopic effect of disproportionation should be less than 16 permil in most sedimentary settings.[17]
Inforest ecosystems, sulfate is derived mostly from the atmosphere; weathering of ore minerals and evaporites 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 inhydrologic studies. Differences in thenatural abundances can be used in systems where there is sufficient variation in the34S of ecosystem components.Rocky Mountain lakes thought to be dominated by atmospheric sources of sulfate have been found to have measurably different34S values than lakes believed to be dominated by watershed sources of sulfate.
The radioactive35S is formed incosmic ray spallation of the atmospheric40Ar. This fact may be used to verify the presence of recent (up to 1 year) atmospheric sediments in various materials. This isotope may be obtained artificially by different ways. In practice, the reaction35Cl +n →35S +p is used by irradiatingpotassium chloride with neutrons.[18] The isotope35S is used in various sulfur-containing compounds as aradioactive tracer for many biological studies, for example, theHershey-Chase experiment.
Because of the weakbeta activity of35S, its compounds are relatively safe as long as they are not ingested or absorbed by the body.[19]
Sulfur vat from which railroad cars are loaded, Freeport Sulphur Co., Hoskins Mound, Texas (1943)Most of the yellow and orange hues ofIo are due to elemental sulfur and sulfur compounds deposited by activevolcanoes.Sulfur extraction, East JavaA man carrying sulfur blocks fromKawah Ijen, a volcano in East Java, Indonesia, 2009
32S is created inside massive stars, at a depth where the temperature exceeds 2.5×109K, by thefusion of one nucleus of silicon plus one nucleus of helium.[20] As this nuclear reaction is part of thealpha process that produces elements in abundance, sulfur is the 10thmost common element in the universe.
Sulfur, usually as sulfide, is present in many types ofmeteorites.Ordinary chondrites contain on average 2.1% sulfur, andcarbonaceous chondrites may contain as much as 6.6%. It is normally present astroilite (FeS), but there are exceptions, with carbonaceous chondrites containing free sulfur, sulfates and other sulfur compounds.[21] The distinctive colors ofJupiter'svolcanic moonIo are attributed to various forms of molten, solid, and gaseous sulfur.[22] In July 2024, elemental sulfur was accidentally discovered to exist onMars after theCuriosity rover drove over and crushed a rock, revealing sulfur crystals inside it.[23]
Sulfur is the fifth most common element by mass in the Earth. Elemental sulfur can be found nearhot springs andvolcanic regions in many parts of the world, especially along thePacific Ring of Fire; such volcanic deposits are mined in Indonesia, Chile, and Japan. These deposits are polycrystalline, with the largest documented single crystal measuring22 ×16 ×11cm (8.7 ×6.3 ×4.3in).[24] Historically,Sicily was a major source of sulfur in theIndustrial Revolution.[25] Lakes of molten sulfur up to about200m (660ft) in diameter have been found on the sea floor, associated withsubmarine volcanoes, at depths where the boiling point of water is higher than the melting point of sulfur.[26]
Native sulfur is synthesized byanaerobic bacteria acting onsulfate minerals such asgypsum insalt domes.[27][28] Significant deposits in salt domes occur along the coast of theGulf of Mexico, and inevaporites in eastern Europe and western Asia. Native sulfur may be produced by geological processes alone. Fossil-based sulfur deposits from salt domes were once the basis for commercial production in the United States, Russia, Turkmenistan, and Ukraine. Such sources have become of secondary commercial importance, and most are no longer worked but commercial production is still carried out in theOsiek mine in Poland.
Common naturally occurring sulfur compounds include thesulfide minerals, such aspyrite (iron sulfide),cinnabar (mercury sulfide),galena (lead sulfide),sphalerite (zinc sulfide), andstibnite (antimony sulfide); and thesulfate minerals, such asgypsum (calcium sulfate),alunite (potassium aluminium sulfate), andbarite (barium sulfate). On Earth, just as upon Jupiter's moon Io, elemental sulfur occurs naturally in volcanic emissions, including emissions fromhydrothermal vents.
↑Steudel,Ralf;Eckert,Bodo(2003).Solid Sulfur Allotropes Sulfur Allotropes. Topics in Current Chemistry.230. pp.1–80.doi:10.1007/b12110.ISBN978-3-540-40191-9.
↑Tebbe,Fred N.;Wasserman,E.;Peet,William G.;Vatvars,Arturs;Hayman,Alan C.(1982)."Composition of Elemental Sulfur in Solution: Equilibrium ofسانچو:Chem, S7, and S8 at Ambient Temperatures".Journal of the American Chemical Society104(18): 4971–4972.doi:10.1021/ja00382a050.Bibcode:1982JAChS.104.4971T.
↑Meyer,Beat(1964)."Solid Allotropes of Sulfur".Chemical Reviews64(4): 429–451.doi:10.1021/cr60230a004.
↑Kim, Ik Soo; Kwak, Seung Im; Park, Ul Jae; Bang, Hong Sik; Han, Hyun Soo (01 جولاءِ 2005),"Production of Sulfur-35 by the Cation Exchange Process", 2005 autumn meeting of the KNS, Busan (Korea, Republic of), 27–28 Oct 2005 (ٻولي ۾ انگريزي)۔
