Question

Out of three metals, sodium, calcium and aluminium, which metal reacts most with water? Give the equation of reaction with all three metals.

Answer 1

1. Sodium metals react rapidly and vigorously with water and liberate hydrogen gas.
   \[\ce{2Na(s) + 2H2O(l) -> 2NaOH(aq) + H2(g) + Heat}\]
2. On the other hand, calcium reacts with water slowly and less vigorously. The hydrogen gas released in this reaction collects on the surface of the metal in the form of bubbles, and the metal floats on water.
   \[\ce{2Ca(s) + 2H2O(l) -> 2Ca(OH)2(aq) + H2(g)}\]
3. Aluminium does not react with cold or hot water but reacts with steam to form oxides. Hydrogen gas is released in this reaction.
   \[\ce{2Al(s) + 3H2O(g) -> Al2O3(s) + 3H2(g)}\]