At home for 5-11 11-14
- Level Elementary
What you need
- A penny or other small coin
- Empty bottle with narrow neck
- Some water
- A freezer
- Put the clean, empty bottle in the freezer for about an hour, or until it’s really cold
- Take the bottle out of the freezer. Wet the mouth of the bottle and quickly put the coin over the mouth, making sure there are no air gaps. Put the bottle back in the freezer for another hour
- Take the bottle out of the freezer and, using a cloth, grasp the bottle with both hands
- Make sure the bottle is pointing away from you and anything breakable!
Results and Explanation
Your hands warm the cold air inside the bottle, making it expand and force the coin off the bottle and into the air!
These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.