The Exploding Lunch Bag

This cool science activity demonstrates the chemical reaction between vinegar and baking soda. Make sure you step outside to try it out!

What you’ll need:

• A re-sealable sandwich bag (freezer bags work the best)
• Baking soda
• Warm water
• Vinegar
• Measuring cups
• Tissue


  1. Put 1/4 cup warm water into the sandwich bag.
  2. Add 1/2 cup of vinegar to the water in the sandwich bag.
  3. Put 3 teaspoons of baking soda in the tissue, then fold it up.
  4. Zip the sandwich bag shut but leave a corner open, enough to fit the tissue full of baking soda in.
  5. Slip the tissue in, quickly seal the bag and step back.
  6. Watch the bag slowly expand and explode!

What’s happening?

After you complete your activity, talk about what happened inside that plastic bag! It takes a little time for the chemical reaction to take place – the tissue gives you some time to seal the bag and step back. When the baking soda and vinegar mix, they create a chemical reaction that produces gas (carbon dioxide in this case). Gas needs more room, which is why you see the bag start to expand and eventually pop! You can take this activity into experiment-mode by trying different variations and comparing what happens.  For example, vary the temperature of the water, the among of baking soda, or the size of the bag, and see how each change affects the result.

This project was inspired by an activity here and here.

Check out other chemical reaction activities from Camp Little Victors: