Balloon Blow-up: Today's STEM Play of the Day

Aug 17, 2020

Even while at home, you can still have fun with science experiments as you would at school or in one of our Ripken STEM Centers. This experiment in today’s STEM Play of the Day from the Ripken Playbook is from our partners, the Boys & Girls Club of the Virginia Peninsula.

Click here to watch a video of today's experiment!

Balloon Blow-up

Typically, when you inflate a balloon, you blow it with helium or oxygen from your lungs. Today you will instead inflate a balloon through a chemical reaction made from a few ingredients you have at home.

*Please use caution when conducting chemistry experiments. Use only the ingredients listed. Do not mix random household products/ingredients. Be sure to conduct this experiment in an easy to clean, open space*


  • Empty water bottle
  • Vinegar 
  • Baking soda 
  • Balloon
  • Safety googles 
    • If none are available, use a pair of sunglasses to protect your eyes.


  1. Fill the water bottle with one to two inches of vinegar.
  2. Stretch the opening of your balloon and place in one tablespoon of baking soda. Make sure it is at the bottom of the balloon, not near the opening.
    1. Tip: If you are having trouble inserting your baking soda into your balloon, try using a funnel, if available.
  3. Carefully stretch the end balloon over the mouth of the water bottle while leaving the baking powder end of the balloon folded over your bottle. 
  4. Grasp the baking powder end of your balloon and sprinkle the baking powder into your bottle. 
  5. Step back! Watch your balloon inflate! 

Understanding the Science! 
Several byproducts (outcomes of a chemical reaction) are produced when you combine baking soda (sodium bicarbonate) and vinegar (acetic acid), one of which is, carbon dioxide (the gas that exits our lungs when we exhale!) As the baking soda and vinegar combine and create a chemical reaction, the carbon dioxide releases as a gas, filling the enclosed balloon. If this chemical reaction were to occur in an open-topped container, the carbon dioxide would appear in the form of bubbles in the reactive solution, however, most of it would escape into the open air.

Experiment Again with These Modifications!
Try repeating this experiment by changing the variables (the ingredients)! 

  • Use the same amount of vinegar but less baking soda. What happened? 
  • Use the same amount of baking soda but less vinegar? What happened? How was it different reaction than the above?
  • Which combination inflates the balloon the fastest? The slowest?
  • What happens if the vinegar is heated? What about if it is cooled?

Don’t forget to share you balloon experiment with us on social media!