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Carbon dioxide gas is everywhere (a fact that sends Al Gore into conniptions) as the product of combustion and biological use of carbon sources like sugars and fats. This means it is easily available for scientific study. As scientists sought to chill this gas, they found that they could not liquefy it at atmospheric pressure, no matter how much they cooled it down. Liquid carbon dioxide only exists at high pressures. That means the solid left no liquid behind as it sublimed – thus the name dry ice.
Dry ice is in common use as the cheapest way to get temperatures well below freezing. Dry ice sublimes at −78.5°C (−109.3°F) which has a wide range of uses – including ice cream and fog machines. (Be careful with the fog – it has elevated CO2 levels and is dangerous without good ventilation.) Two of these uses are ones I encounter regularly in the lab.