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Author Topic: Why does supercooled water stay liquid?  (Read 3928 times)

@LHCollision

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Why does supercooled water stay liquid?
« on: 05/04/2011 06:30:02 »
@LHCollision asked the Naked Scientists:
   
Could you explain to me exactly how supercooled water can stay liquid even temperatures well below freezing?

What do you think?
« Last Edit: 05/04/2011 06:30:02 by _system »


 

Offline freecw

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Why does supercooled water stay liquid?
« Reply #1 on: 04/05/2011 07:20:05 »
Low pressure.
Also, for water to freeze you need to form exact hydrogen bond lengths between the molecules to create the crystal structure of ice. If you added some solutes in water it can disrupt the formation of these bonds so the water remains liquid.
 

Offline Geezer

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Why does supercooled water stay liquid?
« Reply #2 on: 04/05/2011 18:01:36 »
I thought it was more the other way around.

Shouldn't the question really be:

"Why does water crystallize at temperatures below 0°C at STP?"

I think it requires some sort of agitation or impurity to trigger the crystallization process. Without those conditions, it will remain liquid.
 

Offline Bored chemist

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Why does supercooled water stay liquid?
« Reply #3 on: 04/05/2011 22:05:26 »
A very tiny ice crystal in water has to push the liquid water away in order to grow. That means it has to overcome the surface tension of the water.
Sometimes a few water molecules' random motion will get them out of the way, but until that happens the ice can't start to form.
 

The Naked Scientists Forum

Why does supercooled water stay liquid?
« Reply #3 on: 04/05/2011 22:05:26 »

 

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