Wednesday, October 24, 2018

// // Leave a Comment

Dry Ice Science Experiment: Smoke Rings!

It's no secret that we love doing dry ice experiments! Not only are experiments with dry ice amazing to watch, they are also super educational. Watch the kids' eyes light up as you make a vortex launcher and shoot dry ice smoke rings across the table!

Getting Ready

The first thing we needed to do was make our dry ice smoke ring launcher. I gathered the following supplies:
  • One empty 12- or 16-ounce plastic bottle
  • Scissors
  • Party balloon
  • Duct tape
Carefully, I cut the bottom of the plastic bottle off and discarded it.

The plastic was a little bit sharp along the cut edges. If you are worried about that you can always file it down or carefully melt the sharp edges with a lit match. Next, I stretched a balloon over the cut end of the plastic bottle. It's important that the balloon is stretched tight, almost like a drum. We secured the balloon onto the bottle with duct tape. Once we had our smoke ring launcher made, we were ready to move on to the fun part: Creating dry ice smoke rings!

Dry Ice and Water

We poured about 1/4 cup warm water into the plastic bottle.

 Using gloves, we added a few small pieces of dry ice to the bottle. Dry ice fog immediately started pouring out the mouth of the bottle as the dry ice sublimated!

 We have done several cool experiments with dry ice and water. It's thrilling enough simply to watch the white fog spill out of its container. What's even more fun is adding dish soap to make a bubble volcano, launching a rocket, creating incredible bubble art, or doing science tricks like inflating a balloon or making a soda geyser erupt! We learned about what makes dry ice fog by doing this experiment with dry ice in oil. It's actually really weird NOT to see dry ice fog spilling out all over the counter! 

Dry Ice Smoke Rings Experiment

Back to the dry ice experiment at hand: Making smoke rings. Once we had a steady stream of dry ice fog flowing from our bottle we were able to make some really cool dry ice smoke rings.

 I pointed the bottle away from my body and tilted it up a little so that the dry ice and water stayed down against the balloon. With my free hand I tapped lightly on the balloon to make puffs of fog burst out of the bottle.

 It took some practice, but we finally figured out how hard and how fast to tap the balloon to make perfect smoke rings shoot out of the bottle. It would be fun next time to set up a lit candle across the table and shoot dry ice vapor rings at it to put it out!

The Science Behind This Dry Ice Experiment

Dry ice is solid carbon dioxide that sublimes to form carbon dioxide gas. However, the vapor you actually see coming off a block of dry ice is made of tiny frozen water droplets in the air. Carbon dioxide gas is invisible. When dry ice and water mix, the bubbles of carbon dioxide actually pick up some of the water from the container. The fog streaming out of the bottle is very similar to a cloud in the sky. It is made of water vapor and carbon dioxide gas. So how are dry ice smoke rings made? The ring of air that shoots out of the mouth of the bottle is actually a flat, rolling vortex of air. A vortex is generated because the air leaving the bottle at the center of the hole is traveling faster than the air leaving around the edge of the hole. That speed difference creates a swirling motion, or vertical vortex, of dry ice vapor that can be seen rolling through the air. Tapping the balloon on the bottle creates the movement of air needed for a vortex to form. The tapered shape of the bottle pushes the moving air together. Cool, right?

This awesome science experiment is brought to you by Crystal:

Crystal is a homeschooling mom of three and the author of AWESOME SCIENCE EXPERIMENTS FOR KIDS. After exchanging an academic career in chemistry to stay home with her own children, she launched The Science Kiddo to focus on sharing science experiments at home. She writes about science, coding, engineering, and math activities for kids.

Happy Educating,

Have you seen HEEP? It is a preschool homeschool curriculum! Learn more here!

I may share at any of these parties!

Never miss another post again!  Sign up for our weekly updates newsletter and get links to all our posts once a week in your inbox!  Sign up here!!