H2O + Zn

Zn reacts with water, but the product depends on the water state/temperature.

• With steam or hot water (high temperature): Zn + H2O -> ZnO + H2 (g)
• With hot water (some conditions): Zn + 2 H2O -> Zn(OH)2 + H2 (which can dehydrate to ZnO + H2O, giving the same net: Zn + H2O -> ZnO + H2)
• In cold water: Reaction is very slow due to a protective oxide layer on Zn.

So, “H2O + Zn” commonly yields hydrogen gas and zinc oxide under appropriate conditions.