Activity Overview
Astonish your family and your friends with this Leak Proof Bag of Water Experiment. Audiences will stand in amazement as you poke pencils straight through plastic bags and nothing leaks out! This is an easy science experiment which takes little to no time at all to perform and utilizes items that you very likely already have around the house. Kids can use this experiment as a before dinner demonstration which will definitely be the highlight of your next family dinner conversation.
Materials Needed
- Ziploc plastic bags
- Very sharp pencils
- Water
How to Do It
- Fill a plastic Ziploc baggie with with water and seal at the top.
- Take your very sharpened pencils and poke them straight through the bag ( through both sides).
- Repeat the process with several pencils so you should have tops and bottoms protruding through both sides of the bag.
- How come the water stays put and does not leak out?
Scientific Explanation
Ziploc baggies are made up of polymers that we call plastic. Polymers are long chains of molecules that are linked together. When you poke the pencil through the bag, the polymers remain bonded through cross linking that seals the hole around the pencil and therefore the water stays inside the bag.