Materials used in construction include steel, aluminum, glass, bricks and concrete. Limestone is a rock dug up from the ground that is used to make concrete. It contains calcium carbonate (CaCO3) and undergoes thermal decomposition when heated, producing calcium oxide (CaO) and carbon dioxide (CO2). This decomposed limestone is then mixed with sand, gravel and water to form concrete, which sets hard. However, concrete is strengthened by reinforcing it with steel bars, creating a composite material that gains the compressive strength of concrete and tensile strength of steel.

1. C2b Construction Materials
Materials that are used in building are called _________________ materials.
e.g. steel made from iron which is extracted from ores
aluminium extracted from ores
glass made by melting sand, limestone and sodium carbonate
bricks made from baked clay
concrete made from limestone
Limestone to Concrete
• Limestone is a rock that can be dug up in ______________.
• The main compound in limestone is ________________________, CaCO3.
• The limestone has to be heated in a _______________.
• It decomposes to produce quicklime ________________, CaO and carbon
dioxide, CO2.
• We call this type of reaction __________________________________.
Word equation:
Symbol equation:
• Limestone is used in these processes:
1. making sodium carbonate (used to make glass)
2. making steel
3. water purification and treatment
Note: The same type of reaction was used in C1a in cooking where baking powder, NaHCO3
decomposes to produce CO2 gas which makes cakes rise.

2. Cement
• Limestone and ___________ are heated together.
• The product is _________________ and mixed with _____________ and
________________.
• It sets _____________.
• Cement is used to stick ________________ together.
Concrete
• Cement can also be used to make concrete.
• It is mixed with ____________, ____________ and ______________
(small stones).
• Concrete on its own is not very strong.
• To strengthen concrete it is _______________ with ______________.
We call this a __________________ material because it is made from
other materials.
• Reinforced concrete is better than non-reinforced concrete because it
has the ___________________ of concrete and _______________ of
steel.
Definitions: (Look these up in the glossary in the back of your book and LEARN them.
Cement
Concrete
Composite
Construction material
Limestone
Thermal decomposition

3. Ore