I'm not sure whether this applies to boats only but I've never seen it at home

RichardS

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I was just demonstrating this to my Son who had never heard of it before .... and I've only ever seen it on the boat but it happens every summer. I wonder if anyone else has ever seen it?

We bought 4 bottles of drinking water in plastic bottles yesterday, the clear plastic PET type, and put one in the fridge for immediate use, albeit it's a bit warm, and the other three I laid in the bottom of the freezer.

When I opened the freezer a few minutes ago I could see that one bottle was frozen because the ice was translucent but the other two were crystal clear. I then knew that I could do the trick.

So I lift one of the bottles carefully out of the freezer and rock it very gently from side to side so my Son can see that it's liquid water. He says something like "That freezer is not very good Dad". I then give the bottle one vigorous shake ..... and the water freezes completely solid and goes translucent in the blink of an eye. Totally 100% solid in a fraction of a second.

"You were saying" I reply, whilst getting out the second liquid bottle and doing the same tick again.

I'm not sure what the mechanism behind this is, possibly something to do with the seeding of crystal growth which I remember from my Chemistry lessons at school, but it's an impressive trick. :)

Presumably it can be done at home as well, unless it's affect by external temp as it's 29.7C here at the moment, but I suppose that I've never put bottles of water in the freezer at home. In fact, we just drink unsoftened tap water.

Richard
 
I was just demonstrating this to my Son who had never heard of it before .... and I've only ever seen it on the boat but it happens every summer. I wonder if anyone else has ever seen it?

We bought 4 bottles of drinking water in plastic bottles yesterday, the clear plastic PET type, and put one in the fridge for immediate use, albeit it's a bit warm, and the other three I laid in the bottom of the freezer.

When I opened the freezer a few minutes ago I could see that one bottle was frozen because the ice was translucent but the other two were crystal clear. I then knew that I could do the trick.

So I lift one of the bottles carefully out of the freezer and rock it very gently from side to side so my Son can see that it's liquid water. He says something like "That freezer is not very good Dad". I then give the bottle one vigorous shake ..... and the water freezes completely solid and goes translucent in the blink of an eye. Totally 100% solid in a fraction of a second.

"You were saying" I reply, whilst getting out the second liquid bottle and doing the same tick again.

I'm not sure what the mechanism behind this is, possibly something to do with the seeding of crystal growth which I remember from my Chemistry lessons at school, but it's an impressive trick. :)

Presumably it can be done at home as well, unless it's affect by external temp as it's 29.7C here at the moment, but I suppose that I've never put bottles of water in the freezer at home. In fact, we just drink unsoftened tap water.

Richard

I have heard about this before and its something to do with the water at a certain temperature needs a bubble or a piece of dust to start the freezing and is shaken will freeze instantly.

Soda water will do the same as the bubbles in the water will come out of solution and allow the ice to attach and start the reaction

http://www.iflscience.com/chemistry/turn-water-ice-instantly/

https://www.stevespanglerscience.com/lab/experiments/instant-freeze-soda-ice/
 
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There's quite a lot on-line about super-cooled water. I suspect the purity of the water is important so it may not work with tap water.
 
I have heard about this before and its something to do with the water at a certain temperature needs a bubble or a piece of dust to start the freezing and is shaken will freeze instantly.

Soda water will do the same as the bubbles in the water will come out of solution and allow the ice to attach and start the reaction

http://www.iflscience.com/chemistry/turn-water-ice-instantly/

https://www.stevespanglerscience.com/lab/experiments/instant-freeze-soda-ice/

Amazing Roger. I've never thought to try and remove the cap and actually pour out the water as I just thought that it would freezer instantly when I removed the cap. I'm going to try the frozen stalagmite trick. ;)

Richard
 
There's quite a lot on-line about super-cooled water. I suspect the purity of the water is important so it may not work with tap water.

Ah .... that explains why I've never seen the same effect in the ice cube tray at home. The only place where we use bottled water is on the boat because my family don't trust the water in the boat tanks and complain that it tastes of "plastic". I think it's fine but some concessions are necessary. :rolleyes:

Richard
 
Is this similar to something I read recently about exploding water in a microwave? apparently if there are no air bubbles in the water it can dangerously overheat?

That's due to the fact that air is compressible and water is not and in heating the water the water will expand and if there is no air to take up the increase volume the water will press on the bottle so much that the bottle will burst.
 
That's due to the fact that air is compressible and water is not and in heating the water the water will expand and if there is no air to take up the increase volume the water will press on the bottle so much that the bottle will burst.

Nope.
https://www.snopes.com/fact-check/boil-on-troubled-waters/
Without nucleation sites, bubbles of steam struggle to form, because surface tension increases the pressure in a bubble.
Raising the pressure raises the boiling point.
The smaller the bubble, the greater the pressure increase. Hence steam can fail to form in the middle of the liquid water.
http://hyperphysics.phy-astr.gsu.edu/hbase/surten2.html
Microwave heating is the ideal way to promote this, as the water is heated evenly across its bulk rather than at the edges as in a pan over a flame.
Once the water is disturbed, a small bubble quickly becomes a large bubble, limited by the latent heat of evaporation.
 
Not the same as I was describing.

Your vase is in on open cup, mine is in a sealed bottle.

Not sure which one pcatterall was talking about.
 
Heating any liquid in a full sealed container would be asking for trouble unless you were very sure the container was going to expand more than the liquid...
 
That's due to the fact that air is compressible and water is not and in heating the water the water will expand and if there is no air to take up the increase volume the water will press on the bottle so much that the bottle will burst.

No! that obvious explanation does not relate to the example I refer to! This concerned water in an open vessel. I recall that in normal heating ( in a pan on a hob) bubbles will form on the edges and mix with the water as it is agitated and the normal boiling occurs. In a microwave this may not occur often with dramatic results!
 
It's basically the same process in the microwave as in the freezer. Water can be supercooled or superheated if there's nowhere for steam or ice crystals to form. when a crystal or a steam bubble does form, the water freezes or boils instantly. The latter has caused a good few visits to A&E, so be careful with that microwave!

Supercooled water:

Superheated water:
 
Don't these hand warmers work on the same principle?

EX0Ep9e.jpg

The filling is solid when discharged, and you drop them in a pan of boiling water to re-energise them, melting the contents.

To activate them you flex the little metal disk inside, and this causes the contents to suddenly start solidifying (freezing?), giving off the stored heat.
 
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