So What Is Dry Ice, Anyway?
Of course, everyone’s heard of dry ice. You probably know that it’s that stuff that makes fake fog for Halloween decorations and parties too. But what is this mysterious substance really? And what can you do with it besides spice up your next Halloween party? As a matter of fact, quite a bit.
Dry Ice Basics
So, for all of the magical properties it seems to have, dry ice is actually just solid carbon dioxide. Sounds crazy, right? It was first discovered in the first half of the 19th century in France, but it wasn’t until almost 200 years later that people actually began to manufacture dry ice for commercial use.
Making Dry Ice
Dry ice is manufactured using a relatively basic process. Gasses containing a high concentration of carbon dioxide are put under pressure and cooled until the carbon dioxide becomes a liquid. Once that happens, the pressure is released somewhat, causing a certain amount of the liquid carbon dioxide to become a vapor.
This rapid vaporization causes the rest of the liquid carbon dioxide to cool even further and solidify. The flake-like substance that forms as a result of this process can then be compacted and turned into either pellets or blocks. These are the two common forms that commercial dry ice takes.
The following video is of a Dry Ice machine starting up.
Dry Ice vs. Water Ice
You may be wondering what the big deal is at this point. After all, regular water ice is cold too, right? Why go to all the trouble of making dry ice when you can just freeze some water? Well, there are actually quite a few situations in which dry ice would be used instead of water ice because of some of its particular properties.
One of the main differences is that, while water ice leaves water behind when it melts, dry ice simply turns directly back into a vapor. Dry ice is also about twice as dense as water ice, meaning that an equivalent weight will take up half the space.
The Many Lives of Dry Ice
But what do people really use dry ice for? Well, we’ll get into specifics on the many uses of dry ice in other articles on this website, but suffice it to say that the uses are almost endless. Dry ice is used in some way in almost every industry, from manufacturing to food service and everything in between.
You can use it for some fun science projects with your kids or to help with some minor car repairs. Dry ice has even been used to “create” weather events. Certain uses of dry ice are even illegal in some states.
Dry Ice Safety
Before you go running out to get dry ice, though, you need to know something about how to handle it safely. Dry ice is necessarily extremely cold. It generally hovers around -110°F, so you should always wear gloves or some other type of protective equipment when touching dry ice. Without a protective barrier, dry ice can damage your skin and even some of the underlying tissue.
So go out there and have fun – but stay safe!