What are the states of matter?
All matter is made of tiny building blocks called particles. Depending on how these particles move and stick together, things are in one of three states: solid, liquid, or gas.
Solids
In a solid, the particles are close and hold their shape. A solid keeps its shape and has a specific size. Examples: ice, a rock, a pencil.
Liquids
In a liquid, the particles move more and slide past each other. A liquid flows and fills the bottom part of its container, but it still has a fixed amount. Examples: water, juice, milk.
Gases
In a gas, the particles move quickly and spread apart. A gas fills the space around it and can even fill a whole room. Examples: air, steam, helium.
How they change
- Melting: solid turns into a liquid when it gets warm, like ice turning to water.
- Freezing: a liquid becomes a solid when it gets very cold, like water turning to ice.
- Vaporization: a liquid becomes a gas when it gets hot, like water boiling to steam.
- Condensation: a gas becomes a liquid when it cools down, like steam turning into water droplets on a window.
Fun and safe ideas
- Ice melting in a bowl: Watch how an ice cube changes to water as it sits in room temperature.
- Steam with adult help: Hold a warm bowl near your hands and notice the mist that forms above the water.
Quick ideas to remember
- Solid keeps its shape
- Liquid fills the bottom of the container
- Gas fills the space around us