Thinking Thursday: How does a diaper work?

How's your summer plan going? Some of you may know that I studied physics in college and one of the things I love is a good science experiment! No...this isn't really physics, it's chemistry...but it's still cool! And the great thing about it, is most of you probably have all the ingredients to do this experiment already lying around the house! Kids love to discover things about their world and through this experiment you can teach them all about how a diaper works. It's perfect for thinking Thursday or another day of your choosing. And yes, you'll be amazed yourself, right along with them.

Science Experiment: How a Diaper Works

Printable Experiment

MATERIALS:

1-2 diapers, any size or style

scissors

Freezer bag

1 tsp. measuring device

Cup or container

Water

PREPARATION:

1. First take the diaper and lay it on a covered surface or outside. This project is messy!

2. Cut through the top lining of the diaper until you see the cottony stuff inside. 

3. Place all of the cottony stuff in the freezer bag and shake the bag vigorously. You will see a powdery white substance start to shake around inside the bag.

4. Pinch the cottony substance up at the top of the bag and shake the powdery stuff to the bottom of the bag.

5. You will be left with the chemical sodium polyacrylate that is responsible for most of the absorption in diapers in the bottom of the bag.

6. Discard the cottony stuff and keep only the powder for the experiment.

EXPERIMENT:

Take 1 teaspoon of the powder you collected from the diaper and place it in a cup or container. Add 1 teaspoon of water to the powder and watch as it is absorbed by the chemical. Keep adding water a teaspoon at a time to see what happens. Eventually you may have to just pour water in it to see how much it holds if your kids get tired of measuring (like mine did). Sodium polyacrylate will hold up to 300 times it's weight! Eventually it will form a gelatin-like substance that you can even hold upside down in the cup. Some science shows use a small amount of this powder to make kids think that when you pour water in a cup it disappears (but really it is stuck in a gelatin-like substance on the bottom of the cup).

Afterwards I let the kids take the gelatiny stuff outside to touch and play with. It really was amazing (and even magical) to see how much water a small amount of Sodium polyacrylate will absorb. And that's why they can make diapers so light but so absorbent. Amazing. Hope your family loves it as much as we did! Have a happy thinking Thursday!