Silver oxide
Crystal packing
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Names | |
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IUPAC name
Silver(I) oxide
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Other names
Silver rust, Argentous oxide, Silver monoxide
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Identifiers | |
3D model (
JSmol ) |
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ChemSpider | |
ECHA InfoCard
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100.039.946 |
EC Number |
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MeSH | silver+oxide |
PubChem CID
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RTECS number
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
Ag2O | |
Molar mass | 231.735 g·mol−1 |
Appearance | Black/ brown cubic crystals |
Odor | Odorless[1] |
Density | 7.14 g/cm3 |
Melting point | 300 °C (572 °F; 573 K) decomposes from ≥200 °C[3][4] |
0.013 g/L (20 °C) 0.025 g/L (25 °C)[2] 0.053 g/L (80 °C)[3] | |
Solubility product (Ksp) of AgOH
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1.52·10−8 (20 °C) |
Solubility | Soluble in acid, alkali Insoluble in ethanol[2] |
−134.0·10−6 cm3/mol | |
Structure | |
Cubic | |
Pn3m, 224 | |
Thermochemistry | |
Heat capacity (C)
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65.9 J/mol·K[2] |
Std molar
entropy (S⦵298) |
122 J/mol·K[5] |
Std enthalpy of (ΔfH⦵298)formation |
−31 kJ/mol[5] |
Gibbs free energy (ΔfG⦵)
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−11.3 kJ/mol[4] |
Hazards | |
GHS labelling: | |
[6] | |
Danger | |
H272, H315, H319, H335[6] | |
P220, P261, P305+P351+P338[6] | |
NFPA 704 (fire diamond) | |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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2.82 g/kg (rats, oral)[1] |
Related compounds | |
Related compounds
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Silver(I,III) oxide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Silver oxide is the chemical compound with the formula Ag2O. It is a fine black or dark brown powder that is used to prepare other silver compounds.
Preparation
Silver oxide can be prepared by combining aqueous solutions of silver nitrate and an alkali hydroxide.[7][8] This reaction does not afford appreciable amounts of silver hydroxide due to the favorable energetics for the following reaction:[9]
With suitably controlled conditions, this reaction can be used to prepare Ag2O powder with properties suitable for several uses including as a fine grained conductive paste filler.[11]
Structure and properties
Ag2O features linear, two-coordinate Ag centers linked by tetrahedral oxides. It is
where HX = HF, HCl, HBr, HI, or CF3COOH. It will also react with solutions of alkali chlorides to precipitate silver chloride, leaving a solution of the corresponding alkali hydroxide.[12][13]
Despite the photosensitivity of many silver compounds, silver oxide is not photosensitive,[14] although it readily decomposes at temperatures above 280 °C.[15]
Applications
This oxide is used in
References
- ^ a b c "Silver Oxide MSDS". SaltLakeMetals.com. Salt Lake Metals. Retrieved 2014-06-08.
- ^ ISBN 0-8493-0594-2.
- ^ ISBN 0849386713.
- ^ a b "Silver oxide".
- ^ ISBN 978-0-618-94690-7.
- ^ a b c Sigma-Aldrich Co., Silver(I) oxide. Retrieved on 2014-06-07.
- ^ O. Glemser and H. Sauer "Silver Oxide" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1037.
- ^ Janssen, D. E.; Wilson, C. V. (1963). "4-Iodoveratrole". Organic Syntheses
{{cite journal}}
: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 4, p. 547. - ISBN 0-12-352651-5.
- .
- ^ US 20050050990A1, Harigae, Kenichi & Shoji, Yoshiyuki, "Fine-grain silver oxide powder", published 2005-03-10
- ^ a b Cotton, F. Albert; Wilkinson, Geoffrey (1966). Advanced Inorganic Chemistry (2nd Ed.). New York:Interscience. p. 1042.
- ^ General Chemistry by Linus Pauling, 1970 Dover ed. p703-704
- ISSN 0002-7863.
- ^ Merck Index of Chemicals and Drugs Archived 2009-02-01 at the Wayback Machine, 14th ed. monograph 8521
External links
- Annealing of Silver Oxide – Demonstration experiment: Instruction and video