Gold(III) oxide

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Gold(III) oxide
IUPAC name
Gold(III) oxide
Other names
Gold trioxide, Gold sesquioxide
ECHA InfoCard 100.013.748
Molar mass 441.93
Appearance red-brown solid
Density 11.34 g/cm3 at 20 °C[1]
Melting point 160 °C (320 °F; 433 K) (decomposes)
insoluble in water, soluble in hydrochloric and nitric acid
Orthorombic, oF40
Fdd2, No. 43[1]
NFPA 704
Flammability code 0: Will not burn. E.g., waterHealth code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentineReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
Except 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

Gold(III) oxide (Au2O3) is the most stable oxide of gold. It is a red-brown, thermally unstable solid that decomposes at 160 °C.[2] The hydrated form is weakly acidic and dissolves in concentrated alkali to form salts that are believed to contain the Au(OH)4 ion.[2]

Anhydrous Au2O3 can be prepared by heating amorphous hydrated gold(III) oxide with perchloric acid and an alkali metal perchlorate in a sealed quartz tube at a temperature of around 250 °C and a pressure of around 30 MPa.[3]


  1. ^ a b Jones, P. G.; Rumpel, H.; Schwarzmann, E.; Sheldrick, G. M.; Paulus, H. (1979). "Gold(III) oxide". Acta Crystallographica Section B. 35 (6): 1435. doi:10.1107/S0567740879006622. 
  2. ^ a b Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0-08-037941-9. 
  3. ^ Jones, Peter G.; Rumpel, Horst; Sheldrick, George M.; Schwarzmann, Einhard (1980). "Gold(III) oxide and oxychloride". Gold Bulletin (open access). 13 (2): 56. doi:10.1007/BF03215453.