Question: How can we model boiling?

Model

As a group model to explain why changing the pressure of the air above the liquid might be changing whether the liquid boils or not.

1. As a class do this together: Label a piece of paper as “Syringe before”. Discuss how to use pennies and oyster crackers to represent air molecules and water molecules. Include a key to represent the type of molecules and the speed of the molecules.
2. Discuss as a class:  Should there be any water molecules in the air above the syringe? Is is possible some water has evaporated already?
3. As a group, make your own copy of the class consensus model for the “Syringe before” on a single piece of paper.
4. As a group, now label a new piece of paper as “Syringe after pulling”. Using the same number of pennies and oyster crackers, make a 2nd physical model showing the state of syringe when the plunger is pulled out and bubbles of water are forming and raising to the top of the liquid.
5. Discuss as a group:  Should there be the same number of water molecules in the air above the syringe as before?