Silver carbonate

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Silver carbonate
Crystal structure of silver carbonate
Sample of microcrystaline silver carbonate
Identifiers
CAS number 534-16-7 YesY
PubChem 92796 YesY
ChemSpider 83768 YesY
UNII V9WU3IKN4Q YesY
EC-number 208-590-3
MeSH silver+carbonate
Jmol-3D images Image 1
Properties
Molecular formula CAg2O3
Molar mass 275.75 g mol−1
Appearance Pale yellow crystals
Odor Odorless
Density 6.077 g/cm3[1]
Melting point 218 °C (424 °F; 491 K)
decomposes from 120 °C[1][4]
Solubility in water 0.031 g/L (15 °C)
0.032 g/L (25 °C)
0.5 g/L (100 °C)[2]
Solubility product, Ksp 8.46·10-12[1]
Solubility Insoluble in alcohol, liquid ammonia, acetates, acetone[3]
Magnetic susceptibility −8.09·10−5 cm3/mol[1]
Structure
Crystal structure Monoclinic, mP12 (295 K)
Trigonal, hP36 (β-form, 453 K)
Hexagonal, hP18 (α-form, 476 K)[5]
Space group P21/m, No. 11 (295 K)
P31c, No. 159 (β-form, 453 K)
P62m, No. 189 (α-form, 476 K)[5]
Point group 2/m (295 K)
3m (β-form, 453 K)
6m2 (α-form, 476 K)[5]
Lattice constant a = 4.8521(2) Å, b = 9.5489(4) Å, c = 3.2536(1) Å (295 K)[5]
Lattice constant α = 90°, β = 91.9713(3)°, γ = 90°
Thermochemistry
Specific
heat capacity
C
112.3 J/mol·K[1]
Std molar
entropy
So298
167.4 J/mol·K[1]
Std enthalpy of
formation
ΔfHo298
−505.8 kJ/mol[1]
Gibbs free energy ΔG −436.8 kJ/mol[1][4]
Hazards
GHS pictograms The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)[6]
GHS signal word Warning
GHS hazard statements H315, H319, H335[6]
GHS precautionary statements P261, P305+351+338[6]
EU classification Irritant Xi
R-phrases R36/37/38
S-phrases S26, S36
Inhalation hazard Irritant
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g., sodium chloride Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
LD50 3.73 g/kg (mice, oral)[7]
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Silver carbonate is the chemical compound with the formula Ag2CO3. Silver carbonate is yellow but typical samples are grayish due to the presence of elemental silver. It is poorly soluble in water, like most transition metal carbonates.

Preparation[edit]

Silver carbonate can be easily prepared by combining aqueous solutions of sodium carbonate with a deficiency of silver nitrate.[8] Freshly prepared silver carbonate is colourless, but the solid quickly turns yellow.[9] It react with ammonia to give the explosive silver fulminate. With hydrofluoric acid, it gives silver fluoride.

Uses[edit]

The principal use of silver carbonate is for the production of silver powder for use in microelectronics. It is reduced with formaldehyde, producing silver free of alkali metals:[9]

Ag2CO3 + CH2O → 2 Ag + 2 CO2 + H2

Silver carbonate is used as a reagent in organic synthesis such as the Koenigs-Knorr reaction. In the Fétizon oxidation, silver carbonate on celite acts as an oxidising agent to form lactones from diols. It is also employed to convert alkyl bromides into alcohols.[8]

References[edit]

  1. ^ a b c d e f g h Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0. 
  2. ^ Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). New York: D. Van Nostrand Company. p. 605. 
  3. ^ Comey, Arthur Messinger; Hahn, Dorothy A. (1921-02). A Dictionary of Chemical Solubilities: Inorganic (2nd ed.). New York: The MacMillan Company. p. 203. 
  4. ^ a b Anatolievich, Kiper Ruslan. "silver nitrate". http://chemister.ru. Retrieved 2014-07-21. 
  5. ^ a b c d Norby, P.; Dinnebier, R.; Fitch, A.N. (2002). "Decomposition of Silver Carbonate; the Crystal Structure of Two High-Temperature Modifications of Ag2CO3". Inorganic Chemistry 41 (14). doi:10.1021/ic0111177. 
  6. ^ a b c Sigma-Aldrich Co., Silver carbonate. Retrieved on 2014-05-06.
  7. ^ a b "Silver Carbonate MSDS". http://www.saltlakemetals.com. Salt Lake City, Utah: Salt Lake Metals. Retrieved 2014-06-08. 
  8. ^ a b McCloskey C. M.; Coleman, G. H. (1955), "β-d-Glucose-2,3,4,6-Tetraacetate", Org. Synth. ; Coll. Vol. 3: 434 
  9. ^ a b Andreas Brumby et al. "Silver, Silver Compounds, and Silver Alloys" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2008. doi:10.1002/14356007.a24_107.pub2

External links[edit]

H2CO3 He
LiCO3 BeCO3 B C (NH4)2CO3,
NH4HCO3
O F Ne
Na2CO3,
NaHCO3,
Na3H(CO3)2
MgCO3,
Mg(HCO3)2
Al2(CO3)3 Si P S Cl Ar
K2CO3,
KHCO3
CaCO3,
Ca(HCO3)2
Sc Ti V Cr MnCO3 FeCO3 CoCO3 NiCO3 CuCO3 ZnCO3 Ga Ge As Se Br Kr
Rb2CO3 SrCO3 Y Zr Nb Mo Tc Ru Rh Pd Ag2CO3 CdCO3 In Sn Sb Te I Xe
Cs2CO3,
CsHCO3
BaCO3   Hf Ta W Re Os Ir Pt Au Hg Tl2CO3 PbCO3 (BiO)2CO3 Po At Rn
Fr Ra   Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Fl Uup Lv Uus Uuo
La2(CO3)3 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Ac Th Pa UO2CO3 Np Pu Am Cm Bk Cf Es Fm Md No Lr