What you need:
- Plastic sandwich bag
- Baking soda
- Vinegar
- Teaspoon
- Measuring cup (1/4 cup)
- Small square of toilet paper or paper towel
- Permanent markers
What you do:
Step 1: Draw a snowman’s face on your plastic bag.
Step 2: Put two teaspoons of baking soda on a small square of toilet paper or paper towel, and wrap it up.
Step 3: Put the baking soda bundle in the plastic bag.
Step 4: Pour 1/4 cup of vinegar into the bag, and seal it quickly.
Step 5: Stand back and watch your snowman grow.
Safety note: Stand a safe distance away from your bag in case it pops. If it does, collect any small pieces of plastic to prevent choking hazards for young children or pets.
Now try this: Use a bigger bag and try different combinations of vinegar and baking soda.
What’s going on: Your snowman expands because of a simple acid-based chemical reaction. Baking soda, or sodium bicarbonate, is a base that reacts with vinegar, which is an acid known as acetic acid. The two substances combine to produce carbon dioxide gas. Carbon dioxide is the gas that we breathe out.
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