Changing states
Changing States of Matter
Matter can change from one state to another when it gains or loses heat energy.
The three main states are:
Solid
Liquid
Gas
1. Melting
When a solid gets heat, it changes into a liquid.
Example:
Ice melts into water.
The particles start moving faster and spread out a little.
2. Freezing
When a liquid loses heat, it changes into a solid.
Example:
Water becomes ice in the freezer.
The particles slow down and come closer together.
3. Evaporation
When a liquid gets heat, it changes into a gas.
Example:
Water becomes water vapor when heated.
Particles move very fast and spread far apart!
4. Condensation
When a gas loses heat, it changes into a liquid.
Example:
Water droplets form on the outside of a cold bottle.
Gas particles slow down and come closer.
5. Sublimation
Some solids change directly into gas without becoming liquid!
Example:
Naphthalene balls (mothballs)
Important Idea
Changes of state are caused by adding or removing heat energy.The matter is still the same substance — only the state changes!