|
iateshaggy
i haxor 360s



Registered: 05/20/05
Posts: 4,709
Loc: 612 Warf Avenue, next to....
Last seen: 2 months, 7 days
|
super-cooled water?
#8857008 - 08/31/08 05:28 PM (15 years, 8 months ago) |
|
|
so i am getting ready for the storm and decided to put a shit load of water bottles in the freezer last night. this after noon i noticed random ones didn't freeze and ones next to them were solid. i took one out to inspect it, and like magic it instantly froze into slush from top to bottom. can anyone explain what this phenomenon is?
-------------------- You are a filipina sex goddess who wants to fuck me until I fall asleep, so then you can tickle my balls and see if the legend of my diamond filled nutsuck is true. I am a white man from costa rica, who smells like lime jello.
I can flash/jtag/repair 360's, pm for details.
|
supra
computerEnthusiast
Registered: 10/26/03
Posts: 6,446
Loc: TEXAS
Last seen: 13 years, 1 month
|
Re: super-cooled water? [Re: iateshaggy]
#8857130 - 08/31/08 06:20 PM (15 years, 8 months ago) |
|
|
i don't know, ive had beer in glass bottles do the same thing, as soon as I pop the top, i could watch the ice form through the side of the bottle. I always thought it had to do something with the pressure, but never really investigated to know for sure.
peace
|
DieCommie


Registered: 12/11/03
Posts: 29,258
|
Re: super-cooled water? [Re: iateshaggy]
#8857165 - 08/31/08 06:32 PM (15 years, 8 months ago) |
|
|
If it is indeed super cooled, then what the fluid lacks is a 'nucleation' site. That is, to form a crystal (which is what ice is) a small seed crystal is needed. If you have pure water with smooth surfaces in its container, then there is nowhere for the crystal to start forming. But if you hit it or open it, you disrupt the delicate balance and crystals start growing spontaneously.
Alternatively, it might simply be the pressure. If your cap is air tight, it changes the pressure the water is under and that may change its freezing point to just lower than your freezer's temperature.
I once had a beer cooling in the freezer, and went to open it up and it froze before my eyes! It was cool, but then I couldnt drink it and when it melted it tasted like shit.
|
iateshaggy
i haxor 360s



Registered: 05/20/05
Posts: 4,709
Loc: 612 Warf Avenue, next to....
Last seen: 2 months, 7 days
|
Re: super-cooled water? [Re: supra]
#8857172 - 08/31/08 06:35 PM (15 years, 8 months ago) |
|
|
ok, so one of my nerd friends just broke it down for me. seems this is caused by very pure water not wanting to freeze till an impurity breaks the water's surface.
Edited by iateshaggy (08/31/08 06:39 PM)
|
johnm214



Registered: 05/31/07
Posts: 17,582
Loc: Americas
|
Re: super-cooled water? [Re: iateshaggy]
#8858171 - 08/31/08 10:58 PM (15 years, 8 months ago) |
|
|
it helps that it is pure water, but the issue isn't breaking the surface it is starting the crystal, like diecommie said.
Liquid water is more compact than ice at the same temperature. Thus their is some changes in the arrangment of the molecules that need to happen before it can form ice. These changes, say a water molecule sepperating from its neighbors or pushing them far enough away to form quasi bonds with a neighbor, takes energy cuz its got to push other molecules away. This takes energy.
If the water isn't disturbed it may not start forming the crystals. You shake it a bit and one molecule will line up with the other fine and start a chain reaction. Same with introducting something for the water to start binding too.
The whole deal is the extra energy the water needs to start to form the crystal. Even though ice is a lower energy state than water, there is still an energetic hill to climb to start forming the ice. This is a higher burden in very pure water, but it can happen any time.
|
Minstrel
Man of Science



Registered: 03/15/05
Posts: 1,974
Loc: Hogtown
|
Re: super-cooled water? [Re: johnm214]
#8859350 - 09/01/08 08:39 AM (15 years, 8 months ago) |
|
|
Yep, supercooled water is pretty neat to witness. I notice it mostly with freezing those favored bottles of water (yuk). It takes some energy to crystallize the water (it's exothermic). When water freezes normally, it forms one big crystal which steadily grows as you keep it in the freezer, but since crystallizing from supercooled water is very fast, it forms many, many tiny crystals. The freezing raises the temperature of the water bounding the crystal, but the crystal can protrude into the bulk layer where the temperature is still favorable to freeze, thus seeding a new point.
Hence, it's slushy Add some sugar and fruit punch crystals and you have a treat!
Edited by Minstrel (09/01/08 08:46 AM)
|
Minstrel
Man of Science



Registered: 03/15/05
Posts: 1,974
Loc: Hogtown
|
Re: super-cooled water? [Re: Minstrel]
#8859377 - 09/01/08 08:50 AM (15 years, 8 months ago) |
|
|
Also, good luck with the storm. I'll pray for you and yours safety.
|
|