Boyle’s Law

Purpose

To demonstrate Boyle’s Law in action using a model set of lungs.

Materials

• Model lungs (located on the shelf over Dr. Hill’s desk)
• New latex sheet (available from Flinn)
• Vacuum chamber with vacuum pump
• Marshmallow
• Collapsible can
• Bunsen burner
• 10 mL of water

Procedure

Model Lungs Demonstration

1. Setup:

• Take the model lungs and explain the setup to the students.
• Cover the top hole of the lungs.

1. Volume Change:

• Stretch out the diaphragm to increase the volume of the lungs.
• Ask students to predict what will happen to the pressure inside the lungs.

1. Pressure Change:

• Remove your finger from the top hole and demonstrate that higher air pressure outside the lungs forces air into the balloons.
• Repeat the process in the opposite direction (decreasing volume).

1. Latex Sheet:

• Ensure that the model lungs have a new latex sheet for proper functioning.

Vacuum Chamber Demonstration

1. Marshmallow Observation:

• Place a marshmallow inside the vacuum chamber.
• Ask students to predict what will happen when the vacuum is applied and then removed.

Collapsing Can Experiment

1. Preparation:

• Place 10 mL of water in the collapsible can.
• Heat the can over a Bunsen burner until all the water has evaporated.

1. Sealing:

• Quickly stopper the can to trap the steam inside.

Conclusion

These demonstrations effectively illustrate Boyle’s Law, showcasing the relationship between pressure and volume in gases.