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  • Hi, I'm Eddie. I'm a formal communicator here in At Bristol

  • In our water cycle workshop we talk about 'Supercooled Water'

  • I've got a demo here for you that's great to try at home.

  • So, you may notice on those cold winter evenings people place salt

  • out on the streets and pavements, because salty water can go well below zero degrees

  • and remain liquid it freezes.

  • We're going to try and get a bottle of fresh water to get well below zero degrees C

  • but still remain a liquid.

  • For your super cooled water demo

  • you need lots and lots of crushed ice,

  • a small bottle of water

  • a beaker with round about 100ml of tapwater

  • plenty of table salt,

  • teaspoon, and a metal cylinder to place all of your ingredients inside.

  • First thing I'm going to do is to pour plenty of crushed ice

  • into the bottom of my metal cylinder then

  • I need five teaspoons salt to sprinkle around

  • I'm going to now place my small water bottle inside

  • Around that water bottle now i need to pack in

  • as much ice as possible.

  • Now, another 5 spoons of salt

  • Next, i'm going to take 100ml of water

  • and add 5 teaspoons of salt to this

  • Stir the mixture around

  • Now i'm going to pour this salty water all around the ice

  • around my bottle

  • Now, if you've got any room

  • add some more ice on top

  • What we do now is just sit and wait for a good 30 minutes

  • and then our supercooled water should be ready

  • The reason why i can get a bottle of fresh water below zero degrees without freezing

  • is because in our bottled water,

  • we have nonucleation points. A nucleation point is simply

  • any impurities inside that bottle of water which is going to allow

  • ice crystals to form around it. Now when I have my bottle of fresh water that is

  • liquid but below zero degrees, if i cause a disturbance

  • like pouring that water over an ice cube, I'm going to create many nucleation sites

  • and that liquid will turn to ice instantly.

  • it's been about 30 minutes now, so let's see if our super cooled water

  • is ready to make some instant ice

  • So there you go. Instant ice, fantastic experiment.

  • Why don't you try at home?

Hi, I'm Eddie. I'm a formal communicator here in At Bristol

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