The 'Limestone' cycle

The 'Limestone' cycle

1. When heated strongly calcium carbonate in limestone decomposes to:

   • Calcium oxide
     • They react to produce calcium hydroxide
       • Alkali. (Can be used to neutralise acids)
         • It's used by farmers to neutralise acidic soils and in industry to neutralise acidic gases.
       • This is not very soluble in water, but dissolves slightly to make Limewater (Calcium hydroxide solution)
         • Calcium hydroxide reacts with CARBON DIOXIDE to produce CALCIUM CARBONATE, the main compound of limestone.
   • carbon dioxide

2. When water is added to calcium oxide

   • Water