Guiding Question: How does heat energy affect water?

  1. Explaining the model. This picture shows a room temperature bottle of water with a cork stuck in the top of the bottle and a glass tube pushed through the cork into the top of the water. Notice the water in the bottle reaches the bottom of the cork. The water line in the glass tube is just below the top of the bottle. In this model, the light will be switched on for 10 minutes. The light bulb gives off light and heat.
  2. Predict what will happen. What do you predict will happen to the water in the bottle? What makes you think that?
  3. The simulation. This simulation shows what happens to water molecules when water is heated. Notice the thermometer inside the bottle, temperature display, glass tube with hole in the top, and light bulb (which is off).
  4. Start Simulation. Click “ON” and notice the time elapsed.
  5. Movement of molecules. Watch the simulation. What do you notice is happening to the water molecules as the water is heated? How would you describe the movement? How would you describe the space between the molecules? Do the molecules themselves get bigger? How much does the temperature increase?
  6. Movement of water in tube. While watching the simulation, notice what happens to the water level in the tube. [It rises].
  7. A model isn’t exactly the real thing. Stop the simulation. Remind students that the simulation is a model. The model is helpful for showing the movement of water molecules; of course, molecules are much smaller than they appear in the simulation and they don’t look like colored dots.
  8. Revisit the Guiding Question. How does heat energy affect water? What is your evidence?