All the objects that we see in the world around us, are made of matter. Matter makes up the air we
breathe, the ground we walk on, the food we eat and the animals and plants that live around us. Even our
own human bodies are made of matter!
Dierent objects can be made of dierent types of matter, or materials. For example, a cupboard (an
object) is made of wood, nails and hinges (the materials). The properties of the materials will aect the
properties of the object. In the example of the cupboard, the strength of the wood and metals make the
cupboard strong and durable. In the same way, the raincoats that you wear during bad weather, are made
of a material that is waterproof. The electrical wires in your home are made of metal because metals are
a type of material that is able to conduct electricity. It is very important to understand the properties of
materials, so that we can use them in our homes, in industry and in other applications. In this chapter, we
will be looking at dierent types of materials and their properties.
Some of the properties of matter that you should know are:
• Materials can be strong and resist bending (e.g. iron rods, cement) or weak (e.g. fabrics)
• Materials that conduct heat (e.g. metals) are called thermal conductors. Materials that conduct
electricity are electrical conductors.
• Brittle materials break easily. Materials that are malleable can be easily formed into dierent shapes.
Ductile materials are able to be formed into long wires.
• Magnetic materials have a magnetic eld.
• Density is the mass per unit volume. An example of a dense material is concrete.
• The boiling and melting points of substance help us to classify substances as solids, liquids or gases at
a specic temperature.
The diagram below shows one way in which matter can be classied (grouped) according to its dierent
properties. As you read further in this chapter, you will see that there are also other ways of classifying
materials, for example according to whether or not they are good electrical conductors