Basic Concepts
In a nutshell: Matter is everything around us, and it can be a solid, liquid, or gas.
## What is Matter?
Matter is anything that takes up space and has weight. Everything around you—your desk, water in a glass, the air you breathe—is matter!
## Three Main States
- **Solid:** Has a definite shape and volume (like an ice cube).
- **Liquid:** Takes the shape of its container but keeps the same volume (like juice).
- **Gas:** Has no definite shape or volume, and spreads out to fill any space (like the air).
## Changing States
Matter can change from one state to another when you heat or cool it! This is called a change of state.
- Melting: Solid to liquid
- Freezing: Liquid to solid
- Evaporation: Liquid to gas
- Condensation: Gas to liquid
## Experiment at Home
- Freeze water to make ice cubes, then watch them melt!
- Boil water and see steam rise from the pot.
Examples
- Ice (solid) melts into water (liquid) and can turn into steam (gas) when heated.
- Juice in a glass will eventually evaporate if left out, turning from liquid to gas.
Key terms
- Matter
- Anything that takes up space and has mass.
- Solid
- A state of matter with a definite shape and volume.
- Liquid
- A state of matter with a definite volume but no definite shape.
- Gas
- A state of matter with no definite shape or volume.