Aurous bromide, AuBr

When auric bromide is heated, bromine is evolved, and aurous bromide left as a green mass. It is also formed by heating auribromic acid, HAuBr₄, the auric bromide formed decomposing at 115° C. Above this temperature it is decomposed into gold and bromine, and reacts with water like aurous chloride. Aqueous hydro- bromic acid converts it into gold and auribromic acid, HAuBr₄:

3AuBr=AuBr₃+2Au;
AuBr₃+HBr=HAuBr₄.

It dissolves in solutions of alkali-metal bromides.