Many of us have seen the classic “erupting volcano” demonstration that is done with baking soda and vinegar. That is a nice demo, and we can enjoy it, but let’s have a little more fun – loud, startling fun.
When baking soda and vinegar mix, there is a chemical reaction that produces carbon dioxide. Since carbon dioxide is a gas at room temperature, it expands. That is where the bubbles come from in the volcano demo. If you don’t let the gas expand, it creates pressure.
We can use that pressure to create a loud bang and a lot of fun! This experiment is part chemistry, part physics, and complete fun.
We are going to use:
- Soda bottles (16 or 20 oz.)
- Don’t use water bottles. The cap will not seal well enough.
- Baking Soda
- A wide open space
If you try to mix the baking soda and vinegar in the soda bottle, it will react before you can get the cap on and create a big mess. In order to avoid this, I first put the vinegar (and maybe some water) in the bottle. Then I wrap the baking soda up in a tissue. Stuff the tissue into the bottle. This will allow you enough time to get the cap on before the reaction starts.
Make sure you fold up the ends of the tissue. If you forget, the baking soda will spill out, the reaction will start, and vinegar will spray all over your kitchen. Meanwhile your wife will laugh hysterically at you as you try to hold your hand over the top and run to the sink. When you let go to drop it into the sink, you will realize that holding your hand over the top built up the pressure. Actually you will only realize this when the bottle fails to fall into the sink, and instead launches onto the stove. At the end of all of this, you will rethink the idea of assembling these inside as your wife shouts, “I wish I had videoed this!”
Once you have successfully assembled the bottles, give them a good shake to make sure that the baking soda is out of the tissue and is reacting with the vinegar. You should be able to feel the pressure building up in the bottle.
The impact combined with the pressure from withing the bottle should cause the bottle to break or the cap to fly off. There will be a loud bang, and the bottle usually goes flying. The bang is louder when the bottle breaks, but it flies farther when the cap comes off. We had one that flew up higher than our 2 story house! (but we didn’t video that one)
Give it a nice high toss, but make sure you throw it out away from you also (unless you like getting covered in vinegar).
You can try adding water with the vinegar. This will give less room for the gas to expand and will increase the pressure.
Try varying the amounts of baking soda and vinegar and see what works best (you weren’t just going to explode one bottle, were you?).
This one flew so far that it landed in our neighbor’s yard!
Instead of exploding, this one just got a small hole in it. I loved the result.
We also tried a 2 liter bottle.
Have fun exploring the science of God’s Creation.