Activity for ages 3 to 8.
If you’re looking for a simple science experiment with a BIG wow factor, you’ve come to the right spot. This science activity uses just a couple of ingredients, takes just moments to complete and has a super exciting finish. Make some magic inflating conversation hearts just in time for Valentine’s Day!
To prep, I grabbed my supplies:
- An empty bottle
- 4 Alka Seltzer tablets for each round
- 1/2 cup water for each round
- A couple balloons
- A Sharpie
Big Brother helped me break two of the Alka Seltzer tablets into small pieces and dropped them into the bottom of the bottle.
Then we brainstormed a couple of our favorite conversation heart messages and I used the Sharpie to draw them on the balloons. Tip: After a little experimenting, I realized that the conversation heart was more crisp and clear if I first blew it up with air, temporarily pinched it closed with my fingers, and then drew the picture. When I tried drawing the conversation heart while it was flat and uninflated, the image stretched too much when the balloon inflated.
The Science Experiment
After making a prediction about what was going to happen, Big Brother carefully poured the water into the bottle. Then I speedily stretched the mouth of the balloon with my fingers and stretched it over the rim of the bottle. We eagerly watched the magic happen.
We repeated the science experiment over and over again until our pack of Alka Seltzer tablets was empty.
The Science Behind It
Similar to the reaction that occurs when you mix baking soda and vinegar, when you pour water on Alka Seltzer tablets, carbon dioxide gas bubbles begin forming. These gas bubbles rise up in the bottle, filling the balloon with carbon dioxide gas.