Interactive Chemistry Worksheets for Students |
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What is a physical change?
Matter exists in one of three physical states - solid, liquid or gas.
In a physical change matter changes state from one physical state to another.
For example when an ice cube melts it changes from the solid state to the liquid state.
Physical changes are easily reversible. In the melted ice cube is put back into the freezer it will change back into a solid.
Key points:
- Matter exists in three physical states - solid, liquid and gas.
- Matter can change from one physical state to another.
- The physical changes of state are easily reversible
- Energy is absorbed or given off during physical changes of state.
What are the physical changes of matter?
- A solid changing to a liquid it is called melting or fusion.
- A liquid changing to a gas is called evaporation.
- A gas changing to a liquid is called condensation.
- A liquid changing to a solid is called solidification or freezing.
- A solid changing to a gas is called sublimation.
Examples of physical changes.
| Physical change | Example |
| Sublimation | Dry ice change from a solid to a liquid |
| Melting or fusion | An ice cube melting |
| Condensation | The formation of dew on grass in the morning |
| Evaporation | A puddle disappearing on a hot day |
| Solidification or freezing | The formation of hail stones |