Learn

Why do bottles behave the way they do? Or rather, why under certain heat and pressure conditions do they do funny things? This experiment is fun and easy to do, so do give it a try!

What You’ll Need:

• One 2 liter plastic bottle
• 1 bowl filled with hot water
• 1 bowl filled with ice water

1. Place the plastic bottle in the hot water without the cap on.
2. When the bottle feels warm put the cap on.
3. Next, place the plastic bottle in the cold water, what happens?

Why This Happens:
If you did it right, once the bottle is placed in cold water it collapses. But why? Well, when the bottle was placed in the hot water, the air inside it became warm. Warm air takes up more space than room temperature air, so it made the bottle expand. When you put the cap on it, it sealed in that specific amount of air. Once the bottle was placed in the cold water, the air cooled, and because cool air doesn’t take up as much space as warm air, the bottle collapsed. Pretty cool way to see air at work!