Leak-Proof Plastic Bag

Here's a fun experiment we tried in class today - it went so well that we are going to show it in assembly on Friday What you need: Plastic Zip Lock Bags Sharp Pencils Water What to do: Fill plastic bag with water and make sure to seal it tight. Gently 'stab' a pencil through the palstic bag until it pierces through the other side.

Surprise, surprise, NO water leaks out!

The Science behind it:

Despite what it looks like, the zipper-lock bag isn't covered in a magical sealant that blocks leaks. Well… not exactly. Plastic bags like these are made out of our favourite kind of materials, polymers! Polymers are long chains of individual molecules, called monomers. (See that? Mono = one. Poly = many. Mers = molecules.) When you puncture these bags with a sharpened pencil, you're essentially separating polymer chains without breaking them. The long chains of molecules than squeeze in tight around the surface of the pencil preventing any sort of leak. Polymers continue to prove an indispensable part of life. - See more at: http://www.stevespanglerscience.com/lab/experiments/leak-proof-bag#sthash.jBCRn21H.dpuf