Question

How is the neutralisation of a carbonate with an acid different from the neutralisation of an oxide or a hydroxide?

Answer 1

Metal carbonates react with acids to give a corresponding salt, carbon dioxide and water.
The reaction can be represented as follows:
Metal carbonate + Acid → Salt + Carbon dioxide + Water
Example:
     Na₂CO₃(s) +  2HCl(aq) → 2NaCl(aq) + H₂O(l)  + CO₂(g)

However, the neutralisation of an oxide or a hydroxide with an acid gives only a salt and water.
Metal oxide + Acid → Salt + Water
 Example:
          Na₂O + 2HCl  → 2NaCl + H₂O
Metal hydroxide + Acid → Salt + Water
 Example:
          NaOH + HCl →  NaCl + H₂O