Silver sulfide is an inorganic compound with the formula Ag 2S. A dense black solid, it is the only sulfide of silver. It is useful as a photosensitizer in photography. It constitutes the tarnish that forms over time on silverware and other silver objects. Silver sulfide is insoluble in most solvents, but is degraded by strong acids. Silver sulfide is a network solid made up of silver (electronegativity of 1.98) and sulfur (electronegativity of 2.58) where the bonds have low ionic character (approximately 10%).
Silver sulfide naturally occurs as the tarnish on silverware. When combined with silver, hydrogen sulfide gas creates a layer of black silver sulfide patina on the silver, protecting the inner silver from further conversion to silver sulfide.[8] Silver whiskers can form when silver sulfide forms on the surface of silver electrical contacts operating in an atmosphere rich in hydrogen sulfide and high humidity.[9] Such atmospheres can exist in sewage treatment and paper mills.[10][11]
Structure and propertiesEdit
Three forms are known: monoclinic acanthite (β-form), stable below 179 °C, body centered cubic so-called argentite (α-form), stable above 180 °C, and a high temperature face-centred cubic (γ-form) stable above 586 °C.[5] The higher temperature forms are electrical conductors. It is found in nature as relatively low temperature mineral acanthite. Acanthite is an important ore of silver. The acanthite, monoclinic, form features two kinds of silver centers, one with two and the other with three near neighbour sulfur atoms.[12] Argentite refers to a cubic form, which, due to instability in "normal" temperatures, is found in form of the pseudomorphosis of acanthite after argentite.
HistoryEdit
In 1833 Michael Faraday noticed that the resistance of silver sulfide decreased dramatically as temperature increased. This constituted the first report of a semiconducting material.[13]
^ abcdTonkov, E. Yu (1992). High Pressure Phase Transformations: A Handbook. Vol. 1. Gordon and Breach Science Publishers. p. 13. ISBN978-2-88124-761-3.
^Comey, Arthur Messinger; Hahn, Dorothy A. (February 1921). A Dictionary of Chemical Solubilities: Inorganic (2nd ed.). New York: The MacMillan Company. p. 835.
^ abcde"Silver sulfide (Ag2S) crystal structure". Non-Tetrahedrally Bonded Elements and Binary Compounds I. Landolt-Börnstein - Group III Condensed Matter. Vol. 41C. Springer Berlin Heidelberg. 1998. pp. 1–4. doi:10.1007/10681727_86. ISBN978-3-540-31360-1.
^ abcdPradyot, Patnaik (2003). Handbook of Inorganic Chemicals. The McGraw-Hill Companies, Inc. p. 845. ISBN978-0-07-049439-8.
^. saltlakemetals.com. Utah, USA: Salt Lake Metals. Archived from the original on 2014-08-10. Retrieved 2014-07-13.
^Zumdahl, Steven S.; DeCoste, Donald J. (2013). Chemical Principles (7th ed.). Cengage Learning. p. 505. ISBN978-1-111-58065-0.
^"Degradation of Power Contacts in Industrial Atmosphere: Silver Corrosion and Whiskers" (PDF). 2002.
^Dutta, Paritam K.; Rabaey, Korneel; Yuan, Zhiguo; Rozendal, René A.; Keller, Jürg (2010). "Electrochemical sulfide removal and recovery from paper mill anaerobic treatment effluent". Water Research. 44 (8): 2563–2571. Bibcode:2010WatRe..44.2563D. doi:10.1016/j.watres.2010.01.008. ISSN 0043-1354. PMID 20163816.
^"Control of Hydrogen Sulfide Generation | Water & Wastes Digest". www.wwdmag.com. 5 March 2012. Retrieved 2018-07-05.
^Frueh, A. J. (1958). The crystallography of silver sulfide, Ag2S. Zeitschrift für Kristallographie-Crystalline Materials, 110(1-6), 136-144.
^"1833 - First Semiconductor Effect is Recorded". Computer History Museum. Retrieved 24 June 2014.
silver, sulfide, inorganic, compound, with, formula, dense, black, solid, only, sulfide, silver, useful, photosensitizer, photography, constitutes, tarnish, that, forms, over, time, silverware, other, silver, objects, insoluble, most, solvents, degraded, stron. Silver sulfide is an inorganic compound with the formula Ag2 S A dense black solid it is the only sulfide of silver It is useful as a photosensitizer in photography It constitutes the tarnish that forms over time on silverware and other silver objects Silver sulfide is insoluble in most solvents but is degraded by strong acids Silver sulfide is a network solid made up of silver electronegativity of 1 98 and sulfur electronegativity of 2 58 where the bonds have low ionic character approximately 10 Silver sulfide NamesIUPAC name Silver I sulfideOther names Silver sulfide Argentous sulfideIdentifiersCAS Number 21548 73 2 Y3D model JSmol Interactive imageChemSpider 145878 NECHA InfoCard 100 040 384EC Number 244 438 2PubChem CID 166738UNII 9ZB10YHC1C NCompTox Dashboard EPA DTXSID60925902 DTXSID80893679 DTXSID60925902InChI InChI 1S 2Ag S q2 1 2 NKey XUARKZBEFFVFRG UHFFFAOYSA N NSMILES S 2 Ag Ag PropertiesChemical formula Ag 2SMolar mass 247 80 g mol 1Appearance Grayish blackish crystalOdor OdorlessDensity 7 234 g cm3 25 C 1 2 7 12 g cm3 117 C 3 Melting point 836 C 1 537 F 1 109 K 1 Solubility in water 6 21 10 15 g L 25 C Solubility product Ksp 6 31 10 50Solubility Soluble in aq HCN aq citric acid with KNO3 Insoluble in acids alkalies aqueous ammoniums 4 StructureCrystal structure Cubic cI8 a form Monoclinic mP12 b form Cubic cF12 g form 3 5 Space group Im3 m No 229 a form 5 P21 n No 14 b form Fm3 m No 225 g form 3 Point group 2 m a form 5 4 m 3 2 m b form g form 3 Lattice constant a 4 23 A b 6 91 A c 7 87 A a form 5 a 90 b 99 583 g 90 ThermochemistryHeat capacity C 76 57 J mol K 6 Std molarentropy S 298 143 93 J mol K 6 Std enthalpy offormation DfH 298 32 59 kJ mol 6 Gibbs free energy DfG 40 71 kJ mol 6 HazardsOccupational safety and health OHS OSH Main hazards May cause irritationGHS labelling Pictograms 2 Signal word WarningHazard statements H315 H319 H335 2 Precautionary statements P261 P305 P351 P338 2 NFPA 704 fire diamond 7 000Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa N verify what is Y N Infobox references Contents 1 Formation 2 Structure and properties 3 History 4 References 5 External linksFormation EditSilver sulfide naturally occurs as the tarnish on silverware When combined with silver hydrogen sulfide gas creates a layer of black silver sulfide patina on the silver protecting the inner silver from further conversion to silver sulfide 8 Silver whiskers can form when silver sulfide forms on the surface of silver electrical contacts operating in an atmosphere rich in hydrogen sulfide and high humidity 9 Such atmospheres can exist in sewage treatment and paper mills 10 11 Structure and properties EditThree forms are known monoclinic acanthite b form stable below 179 C body centered cubic so called argentite a form stable above 180 C and a high temperature face centred cubic g form stable above 586 C 5 The higher temperature forms are electrical conductors It is found in nature as relatively low temperature mineral acanthite Acanthite is an important ore of silver The acanthite monoclinic form features two kinds of silver centers one with two and the other with three near neighbour sulfur atoms 12 Argentite refers to a cubic form which due to instability in normal temperatures is found in form of the pseudomorphosis of acanthite after argentite History EditIn 1833 Michael Faraday noticed that the resistance of silver sulfide decreased dramatically as temperature increased This constituted the first report of a semiconducting material 13 Silver sulfide is a component of classical qualitative inorganic analysis 14 References Edit a b Lide David R ed 2009 CRC Handbook of Chemistry and Physics 90th ed Boca Raton Florida CRC Press ISBN 978 1 4200 9084 0 a b c d Sigma Aldrich Co Silver sulfide Retrieved on 2014 07 13 a b c d Tonkov E Yu 1992 High Pressure Phase Transformations A Handbook Vol 1 Gordon and Breach Science Publishers p 13 ISBN 978 2 88124 761 3 Comey Arthur Messinger Hahn Dorothy A February 1921 A Dictionary of Chemical Solubilities Inorganic 2nd ed New York The MacMillan Company p 835 a b c d e Silver sulfide Ag2S crystal structure Non Tetrahedrally Bonded Elements and Binary Compounds I Landolt Bornstein Group III Condensed Matter Vol 41C Springer Berlin Heidelberg 1998 pp 1 4 doi 10 1007 10681727 86 ISBN 978 3 540 31360 1 a b c d Pradyot Patnaik 2003 Handbook of Inorganic Chemicals The McGraw Hill Companies Inc p 845 ISBN 978 0 07 049439 8 MSDS of Silver Sulfide saltlakemetals com Utah USA Salt Lake Metals Archived from the original on 2014 08 10 Retrieved 2014 07 13 Zumdahl Steven S DeCoste Donald J 2013 Chemical Principles 7th ed Cengage Learning p 505 ISBN 978 1 111 58065 0 Degradation of Power Contacts in Industrial Atmosphere Silver Corrosion and Whiskers PDF 2002 Dutta Paritam K Rabaey Korneel Yuan Zhiguo Rozendal Rene A Keller Jurg 2010 Electrochemical sulfide removal and recovery from paper mill anaerobic treatment effluent Water Research 44 8 2563 2571 Bibcode 2010WatRe 44 2563D doi 10 1016 j watres 2010 01 008 ISSN 0043 1354 PMID 20163816 Control of Hydrogen Sulfide Generation Water amp Wastes Digest www wwdmag com 5 March 2012 Retrieved 2018 07 05 Frueh A J 1958 The crystallography of silver sulfide Ag2S Zeitschrift fur Kristallographie Crystalline Materials 110 1 6 136 144 1833 First Semiconductor Effect is Recorded Computer History Museum Retrieved 24 June 2014 Greenwood Norman N Earnshaw Alan 1997 Chemistry of the Elements 2nd ed Butterworth Heinemann ISBN 978 0 08 037941 8 External links EditTarnishing of Silver A Short Review V amp A Conservation Journal Images of silver whiskers NASA nbsp Wikimedia Commons has media related to Silver sulfide nbsp This inorganic compound related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Silver sulfide amp oldid 1179307596, wikipedia, wiki, book, books, library,
