Supercooling a liquid is a really neat way of keeping the liquid a liquid below the freezing temperature. Normally, when you decrease the temperature of water below 32oF, it turns into ice. But if you do it gently and slowly enough, it will stay a liquid, albeit a really cold one!
In nature, you’ll find supercooled water drops in freezing rain and also inside cumulus clouds. Pilots that fly through these clouds need to pay careful attention, as ice can instantly form on the instrument ports causing the instruments to fail. More dangerous is when it forms on the wings, changing the shape of the wing and causing the wing to stop producing lift. Most planes have de-icing capabilities, but the pilot still needs to turn it on.
We’re going to supercool water, and then disturb it to watch the crystals grow right before our eyes! While we’re only going to supercool it a couple of degrees, scientists can actually supercool water to below -43oF!
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Materials:
- water
- glass
- bowl
- ice
- salt
Download Student Worksheet & Exercises
Don’t mix up the idea of supercooling with “freezing point depression”. Supercooling is when you keep the solution a liquid below the freezing temperature (where it normally turns into a solid) without adding anything to the solution. “Freezing point depression” is when you lay salt on the roads to melt the snow – you are lowering the freezing point by adding something, so the solution has a lower freezing point than the pure solvent.
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u called the salt water and the water is super cold and yummy (*-*)
The usual problem is that the water wasn’t cold enough. Please make sure that the ice is higher than the water level in the glass. Be sure you are using crushed ice, and put a good amount of salt over the ice. If you still can’t get a it work, please take a picture of your bowl, glass and ice setup, and email it to [email protected]m.
Sure, you can use a metal bowl. Just use gloves if you pick up the bowl. It will be very cold!
arua help I did the experiment exactly how the video said and it didn’t work nothing happened when I dropped the ice cube in do you have any ideas of what could have gone wrong?
can I use a metal bowl?
Sure, you can use a mason jar as your glass cup.
Can I use a mason jar instead of a glass?
No, you should not drink this. This is an experiment, and you may have used your glass for other experiments with substances that are not safe.
Can I drink the ice crystals after they melt?
U Called the salt water.: )