4.4 - Thermal Decomposition of Carbonates

Thermal decomposition of metal carbonates

• Thermal decomposition is when a substance breaks down on heating.
• When a metal carbonate is heated, it decomposes into a metal oxide and carbon dioxide:
  • metal carbonate → metal oxide + carbon dioxide

Decomposing copper(II) carbonate

• Copper(II) carbonate is a green powder that decomposes easily on heating to form black copper(II) oxide and carbon dioxide gas.
• The visible colour change is from green to black.
• copper(II) carbonate → copper(II) oxide + carbon dioxide
• CuCO₃(s) → CuO(s) + CO₂(g)