I read that ice can expand up to 15 tons per square inch. If the water was contained in a vessal that could not expand would it still be able to freeze? Need some help here on the physics.
A quick search on the net gives us this page on the phyics of ice
http://www.cco.caltech.edu/~atomic/snowcrystals/ice/ice.htm
And it has cool pictures of snow flakes too! Bonus!
Anyway, I finally found the right answer. It’s here. No wonder you needed some help. I was lost by the fifth word.
For example:
I don’t know if a similar result holds for the planar regular hexagonal lattice. The problem of computing f(N) and h(N) is the same as counting nowhere-zero flows modulo 3 on L [5,11,12]. Mihail & Winkler [13] have studied related computational complexity issues. No one appears to have enumerated nowhere-zero flows modulo k, where k > 3.
Colin’s links lost me by the third word.
Back in the depths of my memory I can recall seeing/reading about something called (I think) an ice grenade. Essentially it’s a hollow cast iron, grapefruit-sized ball fitted with a screw-on plug; the thing is filled with H2O, plugged, and allowed to freeze, whereupon it will burst upart. (Whether it will do so violently or no, I can’t say.)
I don’t think the ice grenade has a practical purpose; it may have been created as a science demonstration. Dunno.
To deal with your question from theoretical perspective… I always assumed that if you had an utterly unyeilding vessel, as the ice/water tried to expand, its inability to do so would increase it’s own pressure; as I remember from H.S. physics, increased pressure on ice lowers its freezing point (that is, makes it revert to liquid phase). Thus, my guess is that it’s uwn pressure would prevent it from turning totally solid.
Both those links are tangential to the OP.
The basic concept needed is the water phase diagram, which simply shows the structure of water in a range of temperatures and pressures. With such a diagram, you could look at water at room temperature and see that it will become solid at about 10,000 atmospheres(~10 kbar). It becomes Ice VI, a different form of ice than the usual I[sub]h[/sub]. Ice VI is about 1.31 times as dense as 4 degree Celcius liquid water. At about 23,000 atmospheres it becomes Ice VII, which is even more dense. A bit of the physics behind this has been discussed previously in the thread expanding freezing water.
Oh, a phase diagram also reveals that the coldest temperature at which water can be liquid is about -20 degrees Celcius, at a pressure of about 2000 atmospheres.
They set one off as a demonstration in one of my freshman physics classes. It was an iron ball filled with water and placed in liquid nitrogen behind a piece of plexiglass. After a couple of minutes it exploded violently.
Thanks very much every one but I am a poor arts major and this detail is wasted on my non scientific maind. In laymans terms if you please.
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They set one off as a demonstration in one of my freshman physics classes. It was an iron ball filled with water and placed in liquid nitrogen behind a piece of plexiglass. After a couple of minutes it exploded violently. **
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A WAG here. It violently exploded because it froze SO RAPIDLY, not because it just froze. The Metal didn’t have time to expand with the water, since it froze so fast. This feels like a Jearl Walker question, and I don’t know if Uncle Cecil is still communing with Jearl. Any physicists out there wanna swipe at my WAG?
Cartooniverse
Cartoon, by definition the water/ice will have the same temperature as the metal shell around it.
About “practical use”. I guess this phenomenon is the basis of natutal weathing/decay and creates potholes in our roadways. Can it be used to create ice-holes for fishing? Or to dig ditches in winter?
Simple answer:
yes, it would freeze solid, no problem. There would be a pressure on the containing vessel, but so what?
The tires on your car probably have 20 -30 psi on them and they don’t blow up (unless you drive a ford Exploder). I routinely test metal fittings to 20000 psi (that’s 10 tons/sqaure inch). No problems there. Just have a nice strong steel sphere.
I’m surprised nobody warned (Tom) to be careful he doesn’t get ice-nine.
See:
http://www.sigmaxi.org/amsci/issues/sciobs96/sciobs96-09ice.html
Gonna take a shot here, although I’m a bit confused by your OP. 15 tons/per square inch is a measure of pressure, so I’m not sure what you mean by “expansion” in this case; this sounds like a fairly steep pressurization of ice to me.
In any case, regarding your question, this would really depend on the environmental conditions to which you are referring. For this thought experiment, assume that the container in question is perfectly rigid and inflexible (it doesn’t “give”).
Taking a look at a simplified water phase diagram, we can see that for any particular temperature, there is a corresponding freezing point (on the line between the liquid and ice states). So, for the sake of argument, choose 0 degress C and 1 ATM of pressure as the freezing point to investigate. At this temperature and pressure, the water inside the container will start to freeze and expand. However, since the container is perfectly rigid, there will be no space into which the freezing water can expand. This will result in a slight increase in the pressure exerted on the freezing water (the expanding water will exert a force on the walls of the container; the walls of the container, being perfectly rigid, will exert an equal an opposite force on the water). Increasing the pressure while maintaing the same temperature will move the state of the water from a point on the freezing line to a point just inside the liquid region. Thus, the water will remain a liquid.
As a previous post mentioned, there is a limit to how far you can take this, since liquid water cannot exist at sufficiently low temperatures and high pressures.
On the phase diagram pointed to by (Tim), the highest pressure attainable by the I[sub]h[/sub] solid phase (the phase with greater volume than liquid water) is 2000 atmospheres, which is about the 15 tons per square inch mentioned in the original post. This does not necessarily mean that this pressure is achievable by freezing a rigid container of water. To figure that out, you need the bulk modulus or compressiblity of the ice and the amount of expansion obtained when freezing with no applied pressure. Then you can figure out how much pressure is required to compress the ice back to the original size of the water.
It turns out that the pressure required to do this is above 15 tons per square inch, so that point on the phase diagram is possible by freezing in a rigid container. While freezing, pressure would increase to as much as 15 tons per square inch, and when the boundary on the phase diagram is reached, some of the H[sub]2[/sub]O would take on a state (either liquid or solid depending on temperature) that is denser than the I[sub]h[/sub] phase of ice. As this occurs the pressure would stop increasing. The result would be a two phase mixture in equilibrium at the pressure (for a given temperature) of the boundary shown on the phase diagram.