In this topic, we are going to show you how to build a pencil and plastic pouch leak proof water model at home for your science project or exhibitions.
This homemade no leak magic bag science experiment is done using materials like Ziploc bag, pencil, and water which is easily available at home at low cost.
How does it work?
Zipper lock plastic bag that we used for this experiment is mostly made out of a polymer called low-density polyethylene (LDPE).
It is the most common material used for packaging materials. Its cost is a low, durable, lightweight, barrier to moisture, and very flexible.
The sharp tip of the pencil easily slips between and pushes apart the flexible strands of polyethylene molecules however strands’ flexible property helps to form a temporary seal against the edge of the pencil.
When the pencil is removed from the zip loc bag a hole in the plastic bag remains because the polyethylene molecules were pushed aside permanently and the water leaks out.
It is easier for stretched plastic to seal around the smooth sides of a round pencil rather than straight edges found on other pencils.
Pencil through a bag of water experiment explanation at home step by step video?
In this video, we will show steps by step video instructions on how to build a pencil and plastic pouch water model at home easy way.
Start by sharpening the pencil and ensure that tips are sharpened at one point.
Fill in the small Ziploc bag one-half full with water and then seal the bag closed. Take two pencils and ensure that they are sharpened at one end.
Make sure you hold the pencil in one hand and the top of the bag in the other hand.
Now you can push the pencil right through one side of the bag and halfway out the other side without spilling a drop.
We will observe that no water leaks through the zip lock bag. Here, long chains of molecules that make up the bag magically seal back around the pencil and prevent water from leaking out.
Materials used in this video are shown below to build a pencil and plastic pouch water model at home by taking the help of your parents.
- Ziploc bag
- Water in a bottle
Questions & Answers
1. How does the No Leak magic bag work?
We can push pencil right through one side of the bag and halfway out the other side of zip loc bag without spilling a drop.
Here the long chains of molecules that make up the bag magically seal back around the pencil and prevent water from leaking out.
2. Why can you put a pencil through a bag of water?
Ziploc bags are made of a polymer hence now water spills from it. When we pierce a sharp pencil through the zip loc bag, it slides in between chain of molecules that make up the polymer and molecule chains make a seal that won’t let the water out.
Pencil and pouch model helps students to learn about the properties of plastic as well as how to make it with easily available materials at home.