Have a Vinegar and Baking Soda Foam Fight

This is a twist on the classic baking soda volcano, where you use the ingredients to make squirtable fountains of foam.

Difficulty: Easy

Time Required: Mere Minutes

Here's How

1. First, you need bottles for everyone. The classic 2-liter bottle is nice because it's compressible and holds a large volume. Gatorade bottles are also good because they have wide mouths, so it's easier to recharge the bottle.
2. Fill each bottle most of the way full of warm water and add a squirt of dishwashing detergent.
3. Gather the rest of the materials you will need: lots of vinegar and baking soda and food coloring if you want colored bubbles. Be advised: adding food coloring could result in staining of clothing and other surfaces.
4. Add some baking soda to the bottle (​a couple of tablespoons or so). Put your hand over the bottle opening and shake it up to get the detergent water all sudsy. Drip a bit of food coloring onto the suds.
5. Note: if you add the food coloring before shaking the detergent water, then the dye will go into the water and the bubbles will be clear. If you add the coloring just prior to adding the vinegar then the bubbles will be deeply colored (which also increases the staining potential).
6. Pour in some vinegar. This starts the reaction. Feel free to give the bottle a little squeeze to help things along. Do NOT seal the bottle with a cap or lid. That basically makes a baking soda bomb, which is dangerous.
7. You can recharge the reaction with more baking soda and then more vinegar. If at any time you feel like shaking up the bottle only do this with your hand over the opening and never cap or seal the bottle.
8. The foam fight part most people figure out on their own. Have fun!

Tips

1. Avoid getting the mixture into your eyes or mouth. If eye contact occurs, rinse the solution out. Don't drink the contents of the foam fight bottle.
2. Avoid contact with unreacted vinegar or undiluted dishwashing detergent. Both can irritate skin and mucous membranes.

What You Need

• empty compressible plastic bottle - no lids
• water
• dishwashing detergent
• baking soda
• vinegar
• food coloring (optional)