What is matter?
Matter is anything that has mass and takes up space (has volume). A book, a cup of water, the air in a balloon and your own body are all matter. Even a gas you cannot see, such as the air around you, is matter because it has mass and fills space.
Key idea
Matter = anything that has mass and occupies space. If it has mass and volume, it is matter.
Matter is made of tiny particles
All matter is built from extremely small pieces called particles. These particles are far too small to see with the naked eye or even with a normal school microscope. An atom is the smallest particle of an element. Particles can also join together to form molecules, such as two hydrogen atoms and one oxygen atom joining to make one water molecule (H₂O).
- Particles are always moving, even in a solid.
- There are spaces between particles.
- The way particles are arranged decides whether matter is a solid, liquid or gas.
Example
A drop of ink spreads through a glass of still water because the moving ink and water particles mix on their own. This shows that particles are always in motion.
Mass and everyday examples
Mass is the amount of matter in an object, measured in kilograms (kg) or grams (g). A large stone has more mass than a small pebble because it contains more matter. Both living things (plants, animals, humans) and non-living things (rocks, water, air) are made of matter.
Remember
- Matter has mass and occupies space.
- All matter is made of tiny moving particles.
- An atom is the smallest particle of an element.
- Both living and non-living things are matter.