| A | B |
|---|
| Gas particles are tightly packed | while liquid particles are spread apart. |
| Liquid particles move freely | while gas particles are fixed in position. |
| *Gas particles move freely and expand to fill their container | while liquid particles are closer and take the shape of their container. |
| Gas particles vibrate in fixed positions | while liquid particles slide past each other. |
| *Water flowing over the land into rivers | lakes |
| Why does a solid have a definite shape | but a liquid does not? |
| Solid particles move freely | while liquid particles are fixed. |
| *Solid particles are tightly packed in fixed positions | while liquid particles can slide past each other. |
| Energy is added to a gas | causing it to become a liquid. |
| *Energy is removed from a gas | causing particles to move closer and form a liquid. |
| Energy is added to a liquid | causing it to evaporate. |
| Energy is removed from a liquid | causing it to freeze. |
| Cloudy nights are colder | preventing frost formation. |
| *Clouds trap heat | keeping the temperature above freezing. |
| Evaporation occurs only at high temperatures | while boiling occurs at any temperature. |
| *Evaporation happens at the surface | while boiling happens throughout the liquid. |
| Boiling occurs only at 0 degrees C | while evaporation occurs above 0 degrees C. |
| Boiling occurs in solids | while evaporation occurs in liquids. |
