Mammoth Memory

Reactions with water: how you remember

Ask yourself:

“What can a metal in the reactivity series possibly produce with water?”

“What can K, Li or Mg + H2O produce?”


Either (metal) hydroxide + Hydrogen
    (metal) OH + H2



Or (metal) oxide + Hydrogen
    (metal) O + H2



Wow, it’s that easy!


Let’s also say that steam separates all the hydrogen from the oxygen, so:

Cold water + reacting metal (metal) hydroxide + Hydrogen
        (metal) OH + H2




Steam + reacting metal (metal) oxide + Hydrogen
        (metal) O + H2


Example 1


Water + Magnesium Magnesium hydroxide + Hydrogen
2H2O + Mg Mg(OH)2 + H2


Example 2

Steam + Magnesium Magnesium oxide + Hydrogen
H2O + Mg MgO + H2


More Info