Combine a fizzing chemical reaction with balloon science! In this easy baking soda and vinegar balloon experiment, kids can inflate a balloon without blowing into it.
The reaction between baking soda and vinegar produces carbon dioxide gas. But where does the gas go, and why does the balloon get bigger? Try the basic experiment first, explore the science behind the reaction, and then turn it into a simple investigation.
Grade Level: Best for K–5. Use it as a simple cause-and-effect science demonstration with younger kids or explore variables and measurement with older students.
Field of Science: Chemistry
What Kids Will Learn
This balloon experiment is a simple way to explore chemical reactions and gases. Kids can observe that:
- Baking soda and vinegar react when mixed.
- The chemical reaction produces carbon dioxide gas.
- Gas takes up space.
- Trapping the gas inside a balloon causes it to inflate.
- Changing the amount of a reactant can affect the results of an experiment.
💡 Quick Science Question: What do you think is filling the balloon? Make a prediction before you begin.
Baking Soda and Vinegar Balloon Experiment
You only need a few simple supplies to set up this classic chemistry experiment at home or in the classroom.
Supplies
- Baking soda
- Vinegar
- Empty plastic water bottle
- Balloon
- Measuring spoons
- Funnel, optional but helpful
💡 Don’t have vinegar? Lemon juice contains citric acid and also reacts with baking soda. Try our citric acid and baking soda experiment to compare the reactions.
How To Inflate A Balloon With Baking Soda And Vinegar
Watch the video:
Step 1: Blow up the balloon slightly and let the air out. Stretching the balloon first makes it easier for the gas to inflate it during the experiment.
Step 2: Use a funnel and measuring spoon to add 2 teaspoons of baking soda to the balloon.
Step 3: Pour vinegar into the plastic bottle until it is about halfway full.
Step 4: Carefully stretch the opening of the balloon over the top of the bottle.
💡 Keep the baking soda inside the balloon until you are ready to begin. Make sure the balloon forms a tight seal around the bottle opening.
Step 5: Lift the balloon so the baking soda falls into the vinegar.
Watch what happens! The mixture will fizz and bubble as the balloon begins to inflate.
💡 Experiment Tip: Gently swirl the bottle to help the baking soda and vinegar mix. Keep the balloon attached while the reaction is fizzing.
🖌 Optional Art Idea: Before setting up the experiment, use a permanent marker to add emojis, faces, shapes, or other designs to the balloon. Try our Valentine heart balloon experiment or Halloween balloon experiment for seasonal versions.
Why Does Baking Soda and Vinegar Inflate a Balloon?
Baking soda and vinegar undergo a chemical reaction when they are mixed.
Baking soda, also called sodium bicarbonate, is a base. Vinegar contains acetic acid. When the acid and base mix, the reaction produces sodium acetate, water, and carbon dioxide gas.
Carbon dioxide gas inflates the balloon. Because the balloon creates a seal around the bottle, the gas cannot easily escape into the surrounding air. Instead, it moves up into the balloon.
As more carbon dioxide enters the balloon, the gas takes up space and pushes against the inside of the balloon. This causes the balloon to expand.
🔎 In simple terms: The reaction makes a gas. The gas gets trapped inside the balloon, inflating it!
Is Baking Soda and Vinegar a Chemical Reaction?
Yes! Mixing baking soda and vinegar causes a chemical change.
One clue that a chemical reaction has occurred is the formation of a gas. The fizzing and bubbling you observe is carbon dioxide gas escaping from the liquid.
👉 This experiment is also a simple way to introduce the states of matter.
- Baking soda is a solid.
- Vinegar is a liquid.
- Carbon dioxide is a gas.
💡 Ask younger kids to identify each state of matter they observe during the experiment.
Turn It Into a Science Investigation
The basic balloon activity demonstrates a chemical reaction. Want to take the science further? Choose one variable to change and measure the results.
Does More Baking Soda Make a Bigger Balloon?
Keep the amount of vinegar the same for every trial.
Try:
- 1 teaspoon baking soda
- 2 teaspoons baking soda
- 3 teaspoons baking soda
- 4 teaspoons baking soda
Use the same size bottle and a new balloon for each trial.
Measure the circumference of each inflated balloon with a flexible measuring tape. You can also wrap a piece of string around the balloon and measure the string with a ruler.
Record the results for each trial.
- Independent Variable: Amount of baking soda
- Dependent Variable: Circumference of the balloon
- Controlled Variables: Amount of vinegar, bottle size, balloon type, and experiment procedure
Before you begin, ask:
🔎 How will changing the amount of baking soda affect the size of the balloon?
Make a prediction before testing.
💡 Think Like a Scientist: More baking soda may not make the balloon bigger forever! At some point, there may not be enough vinegar available to react with all the baking soda. This is called a limiting reactant.
What do you notice as you increase the amount of baking soda?
More Balloon Experiment Questions To Test
Once you’ve completed the basic investigation, choose a new question to explore.
- Does the amount of vinegar affect the size of the balloon?
- Does the temperature of the vinegar affect how quickly the balloon inflates?
- Does lemon juice produce as much gas as vinegar?
- Does the size of the bottle change the results?
- How long does the chemical reaction take to finish?
💡 Science Tip: Change only one variable at a time. Keeping everything else the same makes it easier to compare your results.
Keep the Chemistry Going!
Want more easy chemistry experiments you can try with simple supplies?
Grab the FREE Chemistry Quick Start Guide for simple experiment ideas, helpful science tips, and an easy way to keep exploring chemistry with kids.
👉 GET THE FREE CHEMISTRY QUICK START GUIDE
Think Like a Scientist
Science isn’t only about watching the balloon inflate. Scientists ask questions about what they observe and look for ways to test their ideas.
Try using the scientific method:
- Ask a question.
- Make a prediction.
- Choose one variable to test.
- Observe and measure.
- Record your data.
- Compare the results.
- Explain what you discovered.
You don’t need a complicated science fair project to practice science skills. A simple activity like this balloon experiment can become an investigation when kids ask a question, test an idea, and use their observations as evidence.
👉 Learn more about the Scientific Method for Kids here.
Baking Soda and Vinegar Balloon Experiment FAQ
Why didn’t my balloon inflate? Check the seal between the balloon and bottle. Carbon dioxide gas can escape through gaps. Also, make sure all the baking soda falls into the vinegar.
Can you use apple cider vinegar? Yes. Apple cider vinegar contains acetic acid and reacts with baking soda. You could compare different types of vinegar as part of an investigation.
Can I use lemon juice instead of vinegar? Yes. The citric acid in lemon juice reacts with baking soda and produces carbon dioxide gas. Compare lemon juice and vinegar to see if you notice a difference.
Why should I stretch the balloon first? Stretching the balloon makes it easier for the carbon dioxide gas to expand the rubber.
Does more baking soda make the balloon bigger? Not always. The amount of carbon dioxide produced depends on the amount of each reactant available. Once there is not enough vinegar to react with additional baking soda, adding more baking soda may not produce significantly more gas.
Is baking soda and vinegar a physical or chemical change? Mixing baking soda and vinegar causes a chemical change because the reaction produces new substances, including carbon dioxide gas.
What gas inflates the balloon? Carbon dioxide, or CO2, inflates the balloon. The gas is produced during the chemical reaction between baking soda and vinegar.
Try More Science With Balloons
Balloons aren’t just for parties! Use them to explore static electricity, air pressure, forces, sound, and chemical reactions with simple hands-on activities.
Explore our science experiments with balloons for more easy ways to investigate science with a simple balloon.
More Chemical Reaction Experiments To Try
Keep exploring chemical reactions with these easy science experiments using simple supplies.
- Baking Soda Volcano: Explore the classic reaction between baking soda and vinegar with an erupting volcano model.
- Dancing Raisins Experiment: Watch carbon dioxide bubbles lift and move raisins through a fizzy liquid.
- Rubber Egg Experiment: Use vinegar to dissolve an eggshell and explore a slower chemical reaction over several days.
- Citric Acid and Baking Soda Experiment: Compare another acid-base reaction and investigate what happens when the ingredients mix.
- Bath Bomb Science: Explore how water helps activate a fizzy reaction between baking soda and citric acid.
- Elephant Toothpaste Experiment: Observe rapid gas production and foam during a completely different type of chemical reaction.
👉 Explore more easy chemical reaction experiments for kids using simple supplies.
Helpful Science Resources
Ready to explore science beyond a single experiment? These resources can help kids ask better questions, test ideas, and record what they discover.
- Scientific Method for Kids
- Free Science Worksheets
- Science Vocabulary
- Science Tools for Kids
- Easy Science Fair Projects
Printable Science Projects for Kids
Want the activity instructions, science information, and investigation pages ready to print?
Our Science Projects Pack includes 90+ classic science activities with supply lists, step-by-step instructions, science explanations, and activity-specific observation pages.
You’ll also find science process resources, vocabulary activities, science journal prompts, and bonus STEAM projects to help you keep the learning going.
EXPLORE THE SCIENCE PROJECTS PACK
Need more info on experiments. Thanks, Miranda
What information would you like?
thanks a lot very funny experiment
Your welcome!
(I was thinking that the pint bottle was going to blow up I got really scared first time I saw a science magic) but I can make smoke come out of my mouth it is very simple
I’m doing a Science Fair Project on this, but I don’t know and how to do the table and graphs, like the data and stuff. Can you help me?
And it’s due May 18, 2016 🙁
this is cool thanks you verry much
Your welcome! Try drawing on the balloons too!
Does the size of the container or size of balloon have any affect on how the balloon will blow up?
Yes, it will because of the space the gas has to fill once the baking soda and vinegar are combined. Great experiment to try different sizes using the same amounts of both vinegar and baking soda.
my team did the balloon inflating thing and it was fun
Is it safe for kids to do this experiment in school
I would think it would be as it is just baking soda and vinegar. You would need to use your best judgement of course. We have never had a balloon explode.
hi this is STEM project .
can anyone explain how to connect – T technology E Engineering M mathematics through this experiment .
thanks in advance
I will look into my information. Remember a STEM project does not need to contain each of the 4 pillars of STEM but at least two. I can tell you we used math {measuring} and science {chemical reaction}.
Definitely is cool
i love yo stuff
If we wanted to use this for a science fair project what would the Question asking be?
How much baking soda/vinegar is needed to inflate balloon completely. Or, which acid is better vinegar or lemon juice? Do different shape balloons fill better?
We just did this experiment, but we only used one balloon. My kids are 2.5, 4 and 7 so we have a range of ability levels, but I wanted to add my kids’ favorite part! We took the balloon off the bottle and tied it shut, careful not to lose the gas. And then I blew a balloon up the same size, I asked them which one they thought would hit the ground first as I held them even in the air. Try it out!!
That’s awesome! We will def have to try that. What a great idea!
Where did you find your containers to hold the baking soda and vinegar?