The thermal decomposition of calcium carbonate produces calcium oxide.
Calcium oxide is known as quicklime.
\(CaCO_3 (s) \rightarrow CaO(s) + CO_2(g)\)
When calcium oxide is reacted with water, calcium hydroxide is produced.
Calcium hydroxide is known as slaked lime. When it is dissolved in water, it is known as limewater.
\(CaO(s) + H_2O(l) \rightarrow Ca(OH)_2(aq)\)
When calcium hydroxide is reacted with carbon dioxide, calcium carbonate is formed.
The calcium carbonate is insoluble in water and this is why limewater can be used to test for the presence of carbon dioxide.
\( Ca(OH)_2(aq)+CO_2(g)\rightarrow CaCO_3 (s) + H_2O(l)\)
Slide 3
Production of Cement
\(\bullet\) Cement is a key ingredient in the manufacture of concrete
\(\bullet\) Limestone and clay are heated strongly, causing the limestone to thermally decompose.
\(\bullet\)The result calcium oxide then reacts with clay to form calcium silicates.
\(\bullet\)Water is added, resulting in a series of complex reactions that form hydrated silicates
\(\bullet\)These make the cement hard
\(\bullet CaCO_3 (s) \rightarrow CaO(s) + CO_2(g)\)
\(\bullet CaO(s) +SiO_2(s) \rightarrow CaSiO_3(s)\)