GCSE Chemistry C1.2 - Limestone & Building Materials

GCSE Chemistry C1.2 - Limestone & Building Materials

1. Limestone

   • Calcium carbonate (CaCO3) also known as Limestone is a sedimentary rock. This can be obtained by quarrying and cut into blocks. It is used as a building material to build walls of houses.
     • Advanatages of quarrying:
       • Creates Jobs
         • Supplies limestone for glass, stell, cement industries in the area
           • Increases business for local workers.
     • Disadvantages of quarrying:
       • Destroys habitats
         • Noise pollution
           • Dust pollution
             • Destroys landscape
               • Dust will destroy local farmers crops
   • Thermal Decomposition
     • Calcium carbonate decomposes on heat to produce calcium oxide and carbon dioxide. This reaction is known as thermal decomposition
     • Other metal carbonates also undergo thermal decomposition, also producing a metal oxide and carbon dioxide gas.
   • Reaction of calcium hydroxide
     • Calcium hydroxide reacts with carbon dioxide to produce calcium carbonate. This reaction is used as a test for carbon dioxide gas (if the limewater AKA Calcium hyrdoxide turns cloudy, the test is positive for carbon dioxide).

2. Cement, Mortar, Concrete

   • Cement - Powdered limestone and powered clay are mixed in a rotary kiln to produce dry cement.
   • Mortar = Cement + sand +water
   • Concrete = Aggragate (crushed rock) + sand + water

3. Reacting Metal Carbonates

   • Metal carbonates + acid --> Salt + Water + Carbon dioxide
     • e.g) Calcium carbonate + Hydrochloric acid --> Calcium Chloride + Water + Carbon Dioxide
       • This means that over time, the metal carbonate, calcium carbonate can be eroded away by acid rain having the potential to destroy buildings.

Imagens e arquivos do mapa