Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Himself on 13/02/2014 23:02:32

Title: Preventing water from freezing?
Post by: Himself on 13/02/2014 23:02:32
This is probably a stupid question, but is there any way to prevent water from freezing in sub-freezing temperatures, i.e. putting it under so much pressure it cannot expand and as a result not freeze?
Title: Re: Preventing water from freezing?
Post by: ScientificSorcerer on 15/02/2014 01:23:25
put it in a vacuum.
Title: Re: Preventing water from freezing?
Post by: RD on 15/02/2014 02:23:41
... is there any way to prevent water from freezing in sub-freezing temperatures, i.e. putting it under so much pressure it cannot expand and as a result not freeze?

Yes very high pressure can lower the freezing point of water below 0oC ,
but requires pressure in the region of 100 to 10,000 times atmospheric pressure  ...

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https://en.wikipedia.org/wiki/Ice#Phases


put it in a vacuum.

Water freezes at a very slightly higher temperature in a vacuum than at atmospheric pressure. (http://van.physics.illinois.edu/qa/listing.php?id=1597)

Being in a vacuum (e.g. in space) does not stop water turning into ice ...
 
Quote from: wikipedia.org/wiki/Comet
The solid, core structure of a comet is known as the nucleus. Cometary nuclei are composed of an amalgamation of rock, dust, water ice, and frozen gases such as carbon dioxide, carbon monoxide, methane, and ammonia
https://en.wikipedia.org/wiki/Comet#Nucleus
Title: Re: Preventing water from freezing?
Post by: evan_au on 15/02/2014 03:51:10
If the water is extremely pure, and is held in a container with no nucleation sites, you can take the temperature of supercooled water (http://en.wikipedia.org/wiki/Supercooled) as low as -48C/-55F before it freezes.

You can put salt in it, or add antifreeze (http://en.wikipedia.org/wiki/Antifreeze).

Some arctic/antarctic fish produce natural antifreeze so they can continue swimming in "freezing" salty ocean water.