1. The Dancing Particles (Diffusion)
This experiment demonstrates how temperature affects particle movement.
Materials:
- 3 clear glasses.
- Potassium Permanganate crystals (or food coloring).
- Hot water, Room temp water, Cold water.
Procedure:
- Fill glass 1 with cold water, glass 2 with room temp water, glass 3 with hot water.
- Drop one crystal of Potassium Permanganate (or a drop of food color) into each glass simultaneously. DO NOT STIR.
- Observe.
Observation:
- Hot Water: The color spreads (diffuses) very quickly.
- Cold Water: The color spreads very slowly, sinking to the bottom first.
Scientific Conclusion: Particles of matter are constantly moving (Kinetic Energy). Heat gives particles more energy, making them move faster. Therefore, diffusion is faster at higher temperatures.
2. Balloon in Hot Water
Materials:
- Empty plastic bottle.
- Balloon.
- Bowl of hot water.
Procedure:
- Stretch the balloon over the mouth of the empty bottle.
- Place the bottle into the bowl of hot water.
Observation: The balloon inflates slightly.
Conclusion: The air inside the bottle is a gas. When heated, the air particles gain energy and move faster/farther apart (Expansion). This increased volume and pressure pushes into the balloon, inflating it.