What's so cool about dry ice?

Dry Ice: The Coolest Stuff on Earth (Except for Maybe Ice Cream)

We're big fans of dry ice at the lab. Here's why:

Dry ice is the solid form of carbon dioxide (CO2), and it's pretty cool. It’s about 50% denser than water ice (H2O). It's also much colder, with a temperature of -78.5 degrees Celsius (-109.3 degrees Fahrenheit). That’s so cold that it can instantly freeze anything it touches. And it's even a little bit dangerous, which is always exciting.

Dry ice does some pretty cool things, like:

• Make fog: When dry ice comes into contact with warm air, it sublimates, which means that it turns from a solid directly into a gas. This process produces a thick, white fog that can be used to create spooky Halloween decorations or to add a touch of mystery to an event like a Science and Sip!

• Freeze stuff: Dry ice is so cold that it can freeze just about anything, including water, food, and even your fingers. This makes it a great tool for science experiments and for making your own ice cream. In our summer science lab, we do just that for instant boozy ice cream! Dry ice is also great for chilled drinks, and because it sublimes into a gas, it doesn't water down or dilute drinks like conventional ice from water.

• Create erupting jets: Mars, Venus, and the moons of Uranus all have layers of dry ice on their surface. On Mars, there are erupting geysers sometimes visible from Earth which occur when carbon dioxide ice quickly frosts and defrosts on its surface.

• Keep stuff away from you: Research shows that part of what attracts mosquitos and other insects to us when they’re looking for a meal is the carbon dioxide we exhale. Because of this, ‘melting’ dry ice gas can be used with traps to attract four to five times as many mosquitoes. A technique used by U.S. soldiers in the Vietnam War.

• Make tires go flat: If you put a piece of dry ice under a tire, it will expand and cause the tire to go flat. This is a classic prank, but it's important to make sure that the car isn't being used at the time...

Unfortunately, there isn’t currently a cheap or safe way to make dry ice at home but if you're looking for a fun and safe way to experiment with dry ice, be sure to check out our next event!

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Sources:

Barber, C.R. (1966). The sublimation temperature of carbon dioxide. British Journal of Applied Physics, 17(3), pp.391–397. doi:https://doi.org/10.1088/0508-3443/17/3/312.

Cartwright, R.J., Emery, J.P., Rivkin, A.S., Trilling, D.E. and N. Pinilla-Alonso (2015). Distribution of CO2 ice on the large moons of Uranus and evidence for compositional stratification of their near-surfaces. Icarus, 257, pp.428–456. doi:https://doi.org/10.1016/j.icarus.2015.05.020.

European Space Agency (2012). A curious cold layer in the atmosphere of Venus. Available at: https://www.esa.int/Science_Exploration/Space_Science/Venus_Express/A_curious_cold_layer_in_the_atmosphere_of_Venus.

National Geographic (2003). Mars Poles Covered by Water Ice, Research Shows.13 February 2003. Available as archived from the original at: http://news.nationalgeographic.com/news/2003/02/0213_030213_marspoles.html on 2009-07-01. Retrieved 2009-07-26.

‌Uigi.com. (2016). Universal Industrial Gases, Inc...CO2 Carbon Dioxide Properties, Uses, Applications  -  Recovery from Industrial Sources - Concentration in Air. Available at: https://www.uigi.com/carbondioxide.html.