We save energy
1. What is matter?
- Matter is everything around us that occupies space. - Each type of matter is called a substance.- Matter can exist in three states: solid, liquid and gas. 
The properties of solids 1. Solids have a fixed shape. 2. Solids occupy the same amount of space. They have a fixed volume. 3 Examples of solids include ice and glass.
Solids can be: 
The properties of liquids1. Liquids do not have a fixed shape. 2. They take the shape
of the container they are in.
They have a fixed volume. Examples of liquids include water and honey
The properties of gases 1. Gases do not have a fixed shape. 2. They take
the shape of the container they are in.
They do not have a fixed volume. They occupy
all the space in the container they are in. Examples of gases include water vapour, oxygen,
and butane gas used for cooking.
2. What are heat and temperature?
The properties of liquids
The properties of gases
Something hotter transfers heat to something colder. This flow causes changes.
Temperature
Temperature is how hot an object is.
The hotter the object, the higher its temperature.
We measure temperature in degrees Celsius (ºC).
We measure temperature with a thermometer.
3. How can matter change?
Changes of state
Substances can change state when they change
temperature.
When we heat an object, its temperature
increases and it expands
. When we stop heating
the object, it cools down and returns
to its original size.
Chemical changes
When a substance changes and produces another different substance, we call it a chemical change
4. What are pure substances
and mixtures?
Matter can be classified into two categories:
pure substances and mixtures
