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Dry Ice Day

NEW FOR 2024: DOWNLOAD updated page as PDF! Great resource for teachers.

Dry Ice is compressed and frozen carbon dioxide. Dry Ice is liquid if stored at 300psi pressure. From there it gets fired into a container where it instantly turns into something resembling snow. The "snow" is then squished down and pressed together forming solid pellets of dry ice. Thanks Air Liquide!

At normal pressure Dry Ice sublimes at -78°C
At that temperature it turns from a solid directly into a gas without going through any liquid state.
This is very useful if you want to keep your picnic lunch cold without also having everything saturated with the water left over from normal ice. When you pick the Dry Ice up from the store, make sure you wind the window in your car down. CO2 gas from Dry Ice does not support breathing ;)

14 Fun Experiments with Dry Ice

Metal Scream
Hold anything metal down on a piece of Dry Ice and listen to the metal scream. I think what's happening is the metal is evapourating a thin layer of gas which pushes the metal up briefly. The resulting vibration results in the noise.

Balloon Popping
Place some pieces inside a balloon and hang it from the ceiling with string. An alternative is to put the balloon in a large container of water - it blows up faster.

Sound Lens?
Apparently if you hold a balloon about a foot from your ear then quiet sounds will be amplified. I'm not sure if this really is the case or if it's just sound bouncing off the outside of the balloon. Experiment with two balloons filled with CO2 and normal air. Careful not to have it explode by your ear.

Film Canister Popping
Place a piece of ice in a film canister on put the cap on. Point the canister away from people.

Film Canister Engine
Push two holes in the bottom of the canister. Push the holes in at an angle so they are pointing out like a pinwheel firework. Add the ice and warm water and hold the canister in the air by trapping a thread under the lid.

Bung Guns
Put some Dry Ice inside a PET (pepsi/coke) bottle with water. Stop it up with a RUBBER BUNG. Then you can either fire the bung into the air or find some way of holding the bottle upside down and the bottle should fly into the air. I definately advise against holding the bottle while firing rubber bungs around.

Magic Water
Mixture of water, a squeze of ammonia, and some universal indicator. It will be a nice blue. Add a small piece of dry ice. Adding more ammonia can make it turn blue again.

Fog
Add lots of Dry Ice to a large beaker half full of boiling water still receiving heat. It makes lots of fog that you can shine lasers through. You could try sniffing the stuff and note that it does note support breathing.

Jet Power
Add Dry Ice to a water bottle with pop-up drinking nozzle (make sure the nozzle is OPEN at all times!!!). The water/CO2 vapour will be firing away nicely but then upend the bottle and see what happens to the water inside the bottle.

Fire Extinguisher
Set something on fire then hold it in a stream of carbon dioxide vapour.

Super Freeze
Add Dry Ice to a beaker of methylated spirits (denatured alcohol). The alcohol does not freeze like water would do so the whole thing becomes a super cooling liquid. Flowers and green leaves will freeze in just a few seconds and can then be broken and snapped apart.

Super Bubbles
Add Dry Ice to a beaker of water and detergent...

Icky Milk Bubbles
Add some Dry Ice to a beaker of milk. If there is any left afterwards, well done. Try tasting it...

Bubble Power
Put some dry ice in a large container. Blow detergent bubbles into the box and watch them float in mid air.