My kids are natural-born scientists. They LOVE to perform experiments. So most days there is something going on in my kitchen or on the side porch that requires my kids to wear their "lab" coats. Most recently, inspired by last week's fireworks during the 4th of July, my son had a blast doing this Nebraska Fizz Project that Little Passports shared with us (I'm a Little Passports Ambassador, remember? So this is my affiliate link). He experimented with his rock collection.
“The fizz test” is a test that uncovers whether rocks in your own backyard have limestone in them. This experiment was inspired by Nebraska, which has the nation’s largest limestone deposit. If a rock contains limestone, you’ll hear that familiar fizzing noise that you hear during a 4th of July fireworks show!
Here's some background information and the instructions for conducting your own experiments. If your family tries this, let us know what your results were!
The Nebraska Fizz Project
The Nebraska Fizz Project
The nation’s largest limestone deposit stands in the Nebraska town of Weeping Water. Limestone is a sedimentary rock (a rock made of compressed, small particles). It contains a compound called sodium carbonate. When you pour acid-based liquids on limestone, the sodium carbonate fizzes, creating a gas called carbon dioxide.
Follow the instructions below to conduct your very own limestone fizz test!
- 3 rocks from your neighborhood
- Damp paper towel
- Pointed object (nail, small shovel or pick)
- 3 tsps vinegar (this is your "acid")
- Dropper or straw
Clean your rocks with the damp paper towel.
Use your pointed object to scratch the surface of each rock. Your goal is to scrape some powder from the rock (not all rocks will be soft enough to allow this—that’s part of your test).
Use your dropper or straw to place about one tsp of vinegar on the area where you scratched. Watch what happens!
- If it's difficult to scratch the rock, and the vinegar doesn't cause a reaction, the rock is NOT limestone.
- If the surface of the rock is easy to scratch, and the surface bubbles or fizzes, it IS limestone!
- If one of your rocks proves to be limestone, it means the ground in your neighborhood is similar to the ground in Nebraska.
- If your rocks aren't limestone, it means the ground in your neighborhood is made of different compounds than the ground in Nebraska.
*Test as many rocks as you'd like!
Disclosure: I'm a Little Passports Ambassador, which means that among other things, from time to time, they provide me with awesome activities and other ideas to share with you, dear readers!