"Not surprisingly, gold is at the top of the series indicating its
high corrosion resistance. In practise, it is corroded only by a
mixture of nitric and hydrochloric acid (aqua regia). In everyday use
gold does not tarnish. Gold only dissolves in cyanide." Courtesy World
"Reaction of gold with air Gold metal is stable in air under normal
conditions. However gold does dissolve in aqueous cyanide solutions in
the presence of air.
Reaction of gold with water Gold does not react with water.
Reaction of gold with the halogens Gold metal reacts with chlorine,
Cl2, or bromine, Br2, to form the trihalides gold(III) chloride,
AuCl3, or gold(III) bromide, AuBr3, respectively. On the other hand,
gold metal reacts with iodine, I2, to form the monohalide gold(I)
2Au(s) + 3Cl2(g) 2AuCl3(s)
2Au(s) + 3Br2(g) 2AuBr3(s)
2Au(s) + I2(g) 2AuI(s)
Reaction of gold with acids Gold metal dissolves in aqua regia, a
mixture of hydrochloric acid, HCl, and concentrated nitric acid, HNO3,
in a 3:1 ratio. The name aqua regia was coined by alchemists because
of its ability to dissolve gold - the "king of metals".
Reaction of gold with bases Gold does not react with aqueous bases."