Four Easy Science Experiments with Vinegar

This experiment is so fun that my daughter used to request I buy extra baking soda and vinegar at the grocery store just for her playtime.

Step 1: Prepare Your "Volcano"

The volcano is optional, but some children like to form a cone from playdough or a glass jar covered in playdough. If you don't want the volcano effect, just select any container. A taller glass vessel really shows off the reaction well.

If you are inside, prepare your surface for a lot of bubbly mess. Use a tray or work in the bathtub or sink. A great option is to work outside so that the mess can be hosed away.

Step 2:  Add Baking Soda

Put baking soda into your dry container. Part of the experiment can be testing different quantities to see how the reaction changes. Let your children have free reign to "waste" some ingredients for the sake of science. Baking soda is ridiculuosly cheap.

Optional -- Add a few drops of food coloring.

Step 3:  Pour in Vinegar

Get ready for some excitement! Pour on the vinegar and watch it bubble, fizz, and foam.

Why it Works

Baking Soda is sodium bicarbonate. Vinegar is acetic acid. When the two are mixed, carbonic acid is formed. That immediately decomposes into water and carbon dioxide. Thus, the bubbly reaction you see is carbon dioxide escaping.

Once your children understand the reaction between baking soda and vinegar, it's fun to adapt the experiment to blow things up!

First you can inflate a balloon with the reaction. 

1.  Use a funnel to add baking soda to a balloon.

2.  Add vinegar to a plastic drink bottle.

3.  Then attach the mouth of the balloon to the mouth of a plastic drink bottle. This part is tricky because you don't want the baking soda to touch the vinegar until the balloon is securely on the mouth of the bottle. So either crimp off the baking soda with a twist tie or just pinch it with your fingers.

4. Holding the balloon securely on, allow the baking soda to fall into the bottle and mix with the vinegar. Watch how the reaction inflates the balloon.

Then you can do a variation of this experiment with a ziplock bag.

1.  Take a double layer of paper towel and mound baking soda in the center. Fold it up in a neat package, with the paper towel protecting the baking soda. You will need to delay the reaction long enough for your to add the vinegar, so wrap it well.

2. Place your baking soda packet into a zip top bag and zip almost closed.

3. Pour vinegar into the bag and quickly seal it. (It might be helpful to use a funnel for this step.)

4. Agitate the bag if the reaction seems slow.

5. Watch the bag inflate and finally explode!

Why it Works

The reasons are the same as in #1 experiment. But the balloon or bag allows you to capture the gas that is emitted during the reaction.

This experiment takes some days to accomplish, but it is worth the wait.

Rubber Bones

Use any leftover bones from your meal. A chicken leg is perfect, but other bones will work too. Remove all meat, gristle, and skin. Completely cover the bone in vinegar in a glass jar. Attach the lid and set aside.

Check the bone after three days, five days, and seven days. It should progressively become more pliable so that you can bend it in half without breaking it.

Disappearing Eggshell

You can use either a fresh egg or a hard boiled egg for this experiment. In fact, you can simply use eggshells themselves and bypass the entire egg. 

1.  Immerse the egg totally in vinegar and let it sit.

2.  After one day, check the egg. Look for bubbles on the shell. Those are carbon dioxide bubble that the reaction creates. Feel the eggshell to see that it is changing.

3.  After three days, check the egg again. By seven days, the eggshell should be completely dissolved. 

Why it Works

Bones and eggshells are hard because of the calcium content in them. Vinegar is an acid (acetic acid) which dissolves calcium. After soaking in the vinegar, the calcium from the bone is dissolved away so that all that is left is the soft tissue which is pliable like rubber.

Eggshells are 94% calcium carbonate, so after the vinegar dissolves the calcium, there is little left except the thin membrane that protects the egg.