Let's do this!
Gloves on! Take a coin then make a deep slit on a piece of dry ice (slightly thicker than the coin), like this,
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| 20 cent coin & dry ice. The dark line on the dry ice is the slit. |
What do you think will happen when we put the coin in the slit?
*first attempt editing a video
Why does the coin vibrate when we put it in a slit on a piece of dry ice?
What is dry ice?
Dry ice is CO2 (carbon dioxide) in solid form. To turn gas into solid, we have to lower the pressure and temperature of the gas.
What will happen if we touch it with our bare hands?
CO2 has to be lowered to -76 to -78°C in order for it to become solid. It is colder than ice. Touching it with our bare hands will in result in a serious frostbite. In room temperature, it is too hot for the dry ice so the dry ice takes the heat from its surrounding to change into its gas form again. By touching it with our bare hands, the dry ice will take up heat from the liquid in our hand, turning it into ice.
When we boil water, the water vapor goes up, means it hot. But when we open our freezer, the water vapor goes down. Looking at the dry ice, water vapor goes down so it is cold.
Why do we call it DRY ice?
I'm not sure the actual origin of the term but I'm sure its more or less because of when we put the dry ice on a piece of tissue, the tissue will stay dry, unlike the ice we put in our milo ice
So, why does the coin vibrate when we put it in a slit on a piece of dry ice?
The dry ice is taking the heat from the coin and turning into gas so quickly from both side of the coin. the releasing of the gas is so rapid that the coin is vibrating.
What do you think will happen when the coin is already cold?
The coin will stop vibrating