Appearance red-brown solid Density 11.34 g/cm³ | Formula Au2O3 | |
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Gold(III) oxide (Au2O3) is the most stable oxide of gold. It is a red-brown, thermally unstable solid that decomposes at 160 °C. The hydrated form is weakly acidic and dissolves in concentrated alkali to form salts that are believed to contain the Au(OH)4− ion.
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.
References
Gold(III) oxide Wikipedia(Text) CC BY-SA