Limestone and Thermal Decomposition

Thermal decomposition of Limestone

• CaCO3 - CaO + CO2
• Calcium Carbonate - Calcium Oxide + Carbon Dioxide
• Heat the carbonate in a boiling tube, then pipe off the gas into a test tube filled with limewater,  Ca(OH)2. The CO2 will turn it milky.
• Some carbonates undergo decompostion more easily and faster than others, depending on the stability

Calcium Hydroxide

• Calcium Oxide + Water - Calcium Hydroxide
• CaO + H2O - Ca(OH)2
• Its an alkali which can neutralise acidic soil, works quickly
• Calcium hydroxide dissolves in water to produce limewater.