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Limestone and building materials. Limestone and building materials. Click to continue. Overview. Rocks provide essential building materials. Limestone is a naturally occurring resource that provides a starting point for the manufacture of glass, cement and concrete.
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Limestone and building materials Limestone and building materials Click to continue
Overview • Rocks provide essential building materials. • Limestone is a naturally occurring resource that provides a starting point for the manufacture of glass, cement and concrete. • Limestone can be thermally decomposed to make new products. Click to continue
Calcium carbonate 1 Limestone is mainly composed of the compound calcium carbonate (CaCO3). It is quarried and can be used as a building material. What are the advantages and disadvantages of using limestone as a building material? Chrispo/Fotolia Click to continue
Calcium carbonate 2 Calcium carbonate can be decomposed by heating (thermal decomposition) to make calcium oxide and carbon dioxide. calcium carbonate → calcium oxide + carbon dioxide CaCO3(s) → CaO(s) + CO2(g) What can calcium oxide be used for? Click to continue
Carbonates The carbonates of magnesium, copper, zinc and calcium decompose on heating in a similar way. What would the equations be for the thermal decomposition of these carbonates? • MgCO3 → • CuCO3 → • CaCO3 → Click to continue
Calcium oxide Calcium oxide reacts with water to produce calcium hydroxide. calcium oxide + water → calcium hydroxide CaO(s) + H2O(l) → Ca(OH)2(s) Calcium hydroxide is an alkali that can be used in the neutralisation of acids. When might it be useful to neutralise acids on a large scale? Click to continue
Calcium hydroxide A solution of calcium hydroxide in water (limewater) reacts with carbon dioxide to produce calcium carbonate. calcium hydroxide solution + carbon dioxide → calcium carbonate + water Ca(OH)2(aq) + CO2(g) → CaCO3(s) + H2O(l) Limewater is used as a test for carbon dioxide. Carbon dioxide turns limewater cloudy. When are tests for carbon dioxide needed? Click to continue
Reactions What are the missing words in this cycle? Click to continue
Calcium carbonate and acid Carbonates react with acids to produce a salt, carbon dioxide and water. Limestone is damaged by acid rain. What would the chemical equation for this reaction be? Click to continue
Cement Limestone is heated with clay to make cement. Cement is mixed with sand to make mortar and with sand and aggregate to make concrete. Click to continue