1. Dry Ice Why is it called DRY ice? Tahoma Jr. High 8 th Grade Science Maple Valley, WA

2. Dry ice “burns” like fire Q: Why? A: Dry “ice” (actually frozen carbon dioxide) is cold: -109 degrees Fahrenheit (-78 degrees Celsius). When you hold dry ice in your bare hand, you freeze the tissues of your skin more and more deeply (“frostbite”). Only a two second exposure starts the process of frostbite – so wear gloves!

3. The skin contains different sensors for cold and heat. The sensors can only tell the difference between cold and heat only within a small temperature range. Touching dry ice overwhelms the sensors and triggers simple pain (not cold or hot).

4. Of course, something this cold is NOT something you would want to swallow – not even a small piece. Be very careful if it is used at parties in drinks. Large pieces cannot be swallowed, but smaller ones can – causing frostbite going down and in your stomach – and can even cause death! (it’s good to know some science!) REGARDLESS - NEVER put anything in your mouth when working in a science lab. You never know what chemicals are around and getting on your hands.

5. The next slide shows what can happen if you put a piece of dry ice into a plastic bottle and screw the cap on tight. DO NOT DO THIS OR ELSE… you may be voluntarily removed from the gene pool !

6. End show