Re: [Phys-l] sudden Vacuum freezing

["Connie Tyree" <CTyree@senecaeast.net>]

I see this happen every winter.  I leave a case of bottled water sit on 
my porch (Northern Ohio) and wait for the temps to drop well below 
freezing.  So far, it has happened each winter since I first observed the 
rapid crystallization.  Pick up a bottle and give it a slight shake or 
slight squeez and watch the water to completely solid within seconds.  My 
husband and I pick up all 24 bottles just to watch the ice form.  It is 
amazing to watch.  I believe allowing to bottles to sit undisturbed so 
close together permits the hydrogen bonding to form but not 
completely...cause a slight disturbance and the bonding pulls the 
molecules into alignment.

-----Original Message-----
From: "fred bucheit" <fbucheit@hotmail.com>
To: phys-l@carnot.physics.buffalo.edu
Date: Mon, 07 May 2007 20:41:44 +0000
Subject: Re: [Phys-l] sudden Vacuum freezing

> Years ago I needed some ice for an experiment the following day in
> Physics 
> class. I placed some water in a standard ice cube tray (back then it
> was 
> aluminum with a removeable aluminum divider) and left for the day. The
> next 
> morning I opened the freezer compartment of the refrigerator and pulled
> out 
> the tray. To my disappointment, the water did not freeze. I decided to
> pour 
> it down a drain on the other side of the room. As I walked across the
> room I 
> happened to look at the tray and I thought I saw something moving in
> the 
> water. It was then I realized that it had supercooled and I was
> watching the 
> crystallization of the water. How many times in a lifetime does one see
> that 
> by accident?
>
> Fred Bucheit....retired
>
> ~I think is the antidote to I believe~
>
>
>
> > Hi,
> >
> > 	For our final lab for or sophomore physics majors, we try to show
> them
> > some odd things like rattlebacks.  We show them how to freeze water in
> a
> > vacuum.  One uses a shallow dish (1/2 inch of water) on a good
> insulator
> > in a vacuum belljar. and start pumping. (This is hard on the pump.) 
> The
> > vapor pressure drops, and the water boils.  The water cools to its
> > freezing point  with the removal of thermal  energy.
> >
> > 	I saw something surprising, at least to see.  The water 
supercooled,
> > and while I was watching it froze in about a second.  It was slow
> enough
> > that I could see a the water-ice boundary move across the dish like
> > almost like a wave.  The dish was then frozen to at least half of its 
> > depth.
> >
> > 	I understand what happened, but am amazed that the water was
> > supercooled to a temperature such that so much water would freeze, and
> > that I happened to be looking at the right moment.
> >
> > Thanks
> >   Roger Haar
> >    Physics U of AZ
> > _______________________________________________
> > Forum for Physics Educators
> > Phys-l@carnot.physics.buffalo.edu
> > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
>
> _________________________________________________________________
> Need a break? Find your escape route with Live Search Maps. 
> http://maps.live.com/default.aspx?ss=Restaurants~Hotels~Amusement%20Par
> k&cp=33.832922~-117.915659&style=r&lvl=13&tilt=-90&dir=0&alt=-1000&scen
> e=1118863&encType=1&FORM=MGAC01
>
> _______________________________________________
> Forum for Physics Educators
> Phys-l@carnot.physics.buffalo.edu
> https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l