Platinum: reactions of elements
Reaction of platinum with air
Platinum metal does not normally react with air or oxygen.
Reaction of platinum with water
Reaction of platinum with the halogens
Careful control of the reaction between platinum metal and fluorine gas, F2, results in either the volatile platinum(VI) fluoride, PtF6 or the tetrameric platinum(V) fluoride, (PtF5)4. The latter posseses the same type of structure as (IrF5)4, (RhF5)4, (OsF5)4, and (RuF5)4, and disproportionates into platinum(VI) fluoride and platinum(IV) fluoride, PtF4.
Pt(s) + 3F2(g) → PtF6(s) [dark red]
4Pt(s) + 10F2(g) → (PtF5)4(s) [deep red]
(PtF5)4(s) → PtF6(s) + PtF4(s) [yellow brown]
The tetrachloride, PtCl4, tetrabromide, PtBr4, and tetraiodide, PtI4, are formed in the reactions of platinum metal and chlorine, Cl2, bromine, Br2, or iodine, I2.
Pt(s) + 2Cl2(g) → PtCl4(s) [red brown]
Pt(s) + 2Br2(g) → PtBr4(s) [brown black]
Pt(s) + 2I2(g) → PtI4(s) [brown black]
The dichloride, platinum(II) chloride, PtCl2, is also formed in the controlled reaction of platinum metal and chlorine, Cl2. Depending upon the reaction conditions, one of two different forms of PtCl2 is formed.
Pt(s) + Cl2(g) → PtCl2(s) [dark red or olive green]