Baking-Soda Volcano
The famous fizzy experiment from the original site—cleaned up, clarified, and still gloriously messy.
What you'll need
- Baking soda—not baking powder
- Vinegar
- A cup, bottle, or other open container
- A tray or outdoor space to catch the overflow
- Paper towels or a cloth, just in case
Instructions
- Place the container on the tray and add a few spoonfuls of baking soda.
- Pour in a small amount of vinegar. Start with less than you think you need.
- Stand back and watch the foamy mixture rise and escape.
What's happening?
Baking soda—sodium bicarbonate—is a base. Vinegar contains acetic acid. When they meet, the reaction produces carbon dioxide gas. The gas forms bubbles, pushes through the liquid, and creates the eruption.
For extra effect, build a volcano shape around the open container using cardboard, paper, or clay. Do not cover the opening.
Turn it into an investigation
Change one thing at a time: the amount of baking soda, the amount of vinegar, or the container shape. Measure how high or how long each eruption lasts, then compare the results.