Things You Probably Didn’t Know About Dry Ice

Dry Ice is a unique substance which has many uses. Essentially, dry ice is frozen carbon dioxide (CO2). The first report of what we now call dry ice came from the French chemist Charles Thilorier, in 1834. In 1924, the DryIce Corporation of America trademarked the solid form of CO2 as “Dry Ice”, which is what it is popularly called today.

The reason that it is called “dry ice” is that is literally is dry – it doesn’t get wet. At normal atmospheric pressures, CO2 changes directly from a solid to a gas. It skips the liquid phase which makes regular ice seem wet.

Frozen CO2 is also much colder than regular ice. Whereas regular ice freezes at 32 degrees Fahrenheit, carbon dioxide changes from a gas to a solid at -109.3 degrees Fahrenheit. This extremely cold temperature makes it very dangerous to handle with bare hands. It can cause frostbite in a very short period of time.

Uses

Dry ice has been used for a wide variety of purposes throughout the past century. The primary use is to refrigerate food when electrical refrigeration isn’t available. Through the process of sublimation (when the CO2 changes from a solid to a gas form), it can maintain cold food for a long period of time.

It is also often used in scientific laboratories for a similar purpose. Frozen CO2 can be used to keep cell tissues and other important materials which are sensitive to heat at a cool temperature.

If you’ve ever been to a haunted house or a play and seen heavy fog on the ground, it is likely that you have seen dry ice in action. This effect can be achieved because carbon dioxide is heavier than air, so evaporated CO2 will sink and accumulate on the ground. This is far superior to most artificial fog machines which use other methods, because the artificial fog will often rise like smoke.

It is also often used by doctors and brave individuals to remove warts and other unsightly blemishes on their skin. By applying a small piece of frozen CO2 and some pressure to a wart, it will effectively freeze and kill the tissue, which allows for easy removal.

Another interesting use for this substance is to bait insects like mosquitoes. These insects have sensors which attract them to carbon dioxide. They find the high concentration of CO2 found in dry ice irresistible.

In the 1960’s scientists guessed that the polar ice caps of Mars are made of frozen carbon dioxide. More recent observations have shown that while the topmost layer consists of frozen CO2, the bulk is probably regular frozen water.

Dangers of Ice Skating

Ice skating is not all glamor and grace. There are also inherent dangers, and all ice skaters, especially the beginners, should be aware of these. In the year 2007 alone, 4,500 skaters were injured in Austria, requiring hospital care. Wrist and head injuries topped the list.

The Fall

Falling on ice is the first danger to be considered, whether skating indoors or outdoors. It not only depends on the skills of the ice skater, but also on the quality of the ice surface, as well the ice skates used. Serious and fatal injuries are very rare, though, but there are isolated cases of paralysis after falling on ice. The skate blades also present one potential cause of danger, as it is very sharp it can slice skin and cause injuries. This emphasizes the need to wear protective gear, especially helmets, for avoidance of head trauma or other similar injuries caused by falling on a skates metal blades.

Skating Outdoors

Moving and gliding on frozen waterways is still an observable fact. As natural ice is unpredictable in terms of strength and structure, there is a potential danger of falling into freezing water whenever the ice breaks. The fact that the ice conditions cannot be controlled should hinder skaters from trying to skate on frozen bodies of water. Once they fall, it will be very hard, if not impossible, to get back onto the ice or out of the water, as the ice tend to break in a continuous manner. This becomes even more hazardous when the skater has no company while skating on naturally-occurring rinks. In the depths of the freezing water, it will be very difficult to swim because of the skates and heavy winter clothing, so there is a big chance for the skater to drown or suffer from shock and hypothermia.

When skating outdoors, one has to remember that the ice is thinner, and therefore weaker, in areas near river or pond edges because of vegetation and higher temperature. Ice is also weak under bridges and areas with most sunlight exposure, also because of warmer temperature.

Because of these ice skating dangers, people need to be educated about wearing appropriate protective gear and, if possible, staying out of frozen waterways when skating, or, if they really want to, they need to know the thickness of the ice first before putting their skates on and starting to move on ice.