Other metals with steam
Metals less reactive than magnesium need steam itself — and for some, even that is not enough.
| Metal | Cold water | Hot water | Steam |
|---|---|---|---|
| Sodium (Na) | rapid reaction | — | — |
| Magnesium (Mg) | no reaction | the hydroxide | the oxide, rapidly |
| Aluminium (Al), zinc (Zn) | no reaction | no reaction | the oxide + H2 |
| Iron (Fe) | no reaction | no reaction | the oxide + H2 |
| Silver (Ag), platinum (Pt), gold (Au) | no reaction | no reaction | no reaction |
Two equations
Aluminium (Al) and zinc (Zn) do not react with cold or hot water, but heated with steam they form the corresponding metal oxide and hydrogen gas.
Zn + H2O → ZnO + H2
Iron too does not react with cold or hot water. Heated with steam it forms the corresponding metal oxide and hydrogen gas.
3Fe + 4H2O ⇌ Fe3O4 + 4H2
The conclusion
The reactivity of metals with water varies from metal to metal. It is fastest for sodium and absent altogether for gold and platinum.
Notice the double-headed arrow in the iron equation — the next page explains it.