National Chemistry Week - Experiments - Brim to Brim

THE AIM:

To show that two pieces of matter cannot be in the same space at the same time.

WHAT YOU WILL NEED:

• 2 identical glasses
• water table or bucket
• water
• drinking straws
• 1 large saucer or pan

WHAT TO DO:

1. Immerse both glasses in the water and fill them both while they are still immersed.
2. Bring the glasses together at their brims, while still under the water.
3. Making sure to keep both glasses together, lift the joined glasses out of the water and place them in the pan.
4. Gently slide the glasses a few millimetres apart.
5. Allow the class to observe that no water falls out of the gap.
6. Take a drinking straw and point it at the gap between the two glasses and blow air through the straw.
7. Make observations.

On its own the water will not seep out through the gap because water likes to stick together. When air is blown into the gap the water moves out of the way to make room for the air, just like the marbles pushed the water up out of their way in the Moved By Marbles experiment.