My kids have had always minor obsessions with balloons, and they’ve always been frustrated by my inability to blow up balloons on command. So when I saw this project on a list of “Amazing Science Projects” on marthastewart.com, I knew it would be perfect for us to try.
First, I had to reinforce the idea that balloons (at least the small ones we have) are really, really hard to blow up for normal mortals. And even for five-year-olds.
Then we gathered the materials needed to create the Magical Balloon Inflater.
Magical Balloon Ingredients
- White vinegar
- Baking soda
- Balloons (don’t want them to be too small, or you won’t be able to fit enough baking soda inside)
- Bottle (with a small enough neck to fit your balloon over it)
- Small funnel (you need this to get the baking soda into the balloon)
First add 4 TBSP of vinegar to the bottle. To make it more kid-doable, we measured the vinegar into the measuring cup, then H poured the vinegar through the funnel into the bottle himself. You don’t absolutely need the funnel for this part, but it does make it easier for a kid to get the vinegar in without spilling.
Forming the Magical Balloon
Then you add the baking soda to the balloon. To do this, slip the end of the balloon over the end of your funnel and measure 1 TBSP of baking soda into the funnel. Our balloons were a little small, so we ended up using a chopstick to get most of the baking soda into the balloon.
Then carefully slip the balloon off the funnel and slide it over the end of the bottle with the vinegar. At this point, you want to make sure the baking soda stays in the balloon hanging over the side of the bottle.
Inflating the Balloon
Now comes the fun part! Holding the mouth end of the balloon pretty tightly onto the bottle, lift up the other end and dump the baking soda into the vinegar. Keep holding onto the balloon – there’s some pressure as it inflates, and you don’t want it to blow off before it’s really inflated.
We had to do it over and over again, of course! We found it worked best to dump out the vinegar & baking soda from the bottle and rinse it a bit between each go-round.
It’s also fun to let go of the balloon and see it whiz around the kitchen. Just be sure nobody’s face is right in front of the balloon, of course. I wasn’t fast enough to capture the balloon in flight, but this is the split second after it was released (you can see the specks of baking soda coming out of the bottle.)
Why It Works
When baking soda and vinegar come into contact, they form carbon dioxide. This gas fills the bottle and can’t escape, so it rushes into the balloon, causing it to inflate.