Chalk Burst Baggies in 5 Steps

Materials you'll need

• Cornstarch
• Vinegar
• Baking soda
• Paper towel
• Ziplock bag
• Food coloring

 

Step-by-step tutorial

Step 1: Add ½ cup of cornstarch to the ziplock bag. Pour in ¾ cup of vinegar. 

Step 2: Add a few drops of food coloring if you'd like a colorful burst. Seal the bag and squish everything together until the mixture is smooth and combined.

Step 3: Place 1 tbsp of baking soda in the center of a paper towel and fold it into a small packet. This slows down how fast the baking soda reaches the vinegar, giving you time to seal the bag.

Step 4: Take everything outside! Partially unzip the bag, drop in the baking soda packet, and seal it up tight right away.

Step 5: Shake, shake, shake — then step back and watch the bag puff up and burst.

Learn more

When baking soda and vinegar mix, they trigger a chemical reaction — that's when two substances combine to make something completely new. In this case, the baking soda (a base) and the vinegar (an acid) react to produce carbon dioxide, the same fizzy gas that makes soda bubbly. Because the bag is sealed shut, the CO₂ has nowhere to go, so it keeps building up inside until the pressure gets too strong — and pop!