Dry Ice-Capades (Nov, 1947)
Dry ice is very interesting stuff! Get yourself a chunk (handling it with gloves) and perform the simple experiments illustrated here.
DRY ice is solid carbon dioxide. It’s very interesting stuff. For one thing, it sublimes at room temperature; that is, although a solid, it evaporates to form a gas without passing through the liquid state. The mist you see formed by dry ice is water “squeezed” out of the air because it has been chilled below the dewpoint.
Dry ice will readily freeze water and other liquids, and is sometimes used to “quick-freeze” food. The water in plant or animal tissues, under proper conditions, freezes very rapidly and the hard, frozen tissue then is brittle and shatters when struck. The “burns” caused by dry ice are really areas where the body fluids have been frozen. Since ice formation is often accompanied by the growth of needle-like crystals, one can see that these frost-bites can be both painful and dangerous. For the sake of safety, dry ice should be handled with gloves or tongs, not with bare hands.
On the following pages are photographs illustrating a few experiments that may be performed with dry ice. Try them!