What happens when metals react with air water and acids?

Answer 1

Do you mean seperately?

If yes, then:

1. When they react with air, it is combustion: 2Ca + O2 --> 2CaO
2. With water, they simply come to be hydroxides: Na + H2O --> NaOH + H2
3. When they react with acids then a salt and hydrogen gas is formed:

   Zn +2HCl --> ZnCl2 + H2

Answer 2

When metals react with air, they can form a layer of oxide on the surface which can protect the metal from further corrosion (e.g., rusting of iron). When metals react with water, they can undergo oxidation to form metal hydroxides and release hydrogen gas. When metals react with acids, they can undergo a displacement reaction where the metal replaces hydrogen in the acid to form a metal salt and release hydrogen gas.

Answer 3

Each metal has a specific behavior.