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Can ice be made by pressure? Would it be warm?

  • 25-11-2009 10:22pm
    #1
    Registered Users, Registered Users 2 Posts: 237 ✭✭


    Just an odd question that's been muddling in my head for a while, how much pressure is require to turn water into ice and would it have the same properties? (Density .ect). Would it be above 1*C?

    Sorry for such a silly question. ;)

    Thanks :D


Comments

  • Closed Accounts Posts: 125 ✭✭Azelfafage


    The Irishman Boyle informed us that water can be solidified at ANY temperature.

    Just put on the pressure!!!

    (Ok ....not inside the sun....water ceases to be water inside the sun.)

    .


  • Closed Accounts Posts: 56 ✭✭ThePirateGay


    It can, artificially, depending on what pressure setting you select on a central flux-capacitor.


  • Moderators, Sports Moderators Posts: 28,138 Mod ✭✭✭✭Podge_irl


    Azelfafage wrote: »
    The Irishman Boyle informed us that water can be solidified at ANY temperature.

    Just put on the pressure!!!

    (Ok ....not inside the sun....water ceases to be water inside the sun.)

    .

    Boyle's Law says nothing of the sort. It doesn't even have anything to do with liquids or solids, only gases.


  • Closed Accounts Posts: 66 ✭✭Myggel




  • Closed Accounts Posts: 125 ✭✭Azelfafage


    Podge_irl wrote: »
    Boyle's Law says nothing of the sort. It doesn't even have anything to do with liquids or solids, only gases.

    Squeeze a gas and it becomes a liquid.

    Squeeze a liquid and it becomes a solid.

    (Ask the Corkman Boyle.)

    The Interior of the planet Jupiter is solid metallic hydrogen.

    .


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  • Moderators, Sports Moderators Posts: 28,138 Mod ✭✭✭✭Podge_irl


    Azelfafage wrote: »
    Squeeze a liquid and it becomes a solid.

    Go squeeze some ice from your freezer and see what happens.

    Boyle's Law still has nothing to do with solids or liquids though. It doesn't even work for gases under all conditions.


  • Closed Accounts Posts: 125 ✭✭Azelfafage


    Podge_irl wrote: »
    Go squeeze some ice from your freezer and see what happens.

    Put it half way to the core of Jupiter and see what happens.

    .


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    Moromaster wrote: »
    Just an odd question that's been muddling in my head for a while, how much pressure is require to turn water into ice and would it have the same properties? (Density .ect). Would it be above 1*C?

    Sorry for such a silly question. ;)

    Thanks :D

    Ok, everyone seems to have lost the plot here (well, except Podge). The phase diagram for water looks as follows:

    water-phase-diagram.jpg

    Increasing pressure actually melts ice, as any ice-skater should be able to tell you. Yes, that is extremely unusual for a substance, but water behaves kind of odd. It happens for exactly the same reason water expands when it freezes. It doesn't matter how much pressure you apply, water is simply denser in it's liquid form, and so more pressure equals liquid. Unless you apply so much pressure you break apart the molecules or cause it to collapse into a neutron star or a black hole. Not something you'll achieve with a vice-grips, or even by dumping it on Jupiter.


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 93,581 Mod ✭✭✭✭Capt'n Midnight


    Ice has a lower density than Water so pressure usually melts it



    from wikipedia - GPa of pressure could work because some forms of Ice have a lower density than water BUT you need to be at very low temperatures, there are many forms of Ice crystals but most are less dense than water


    High-density amorphous ice (HDA) can be formed by compressing ice Ih at temperatures below ~140 K. At 77 K, HDA forms from ordinary natural ice at around 1.6 GPa[3] and from LDA at around 0.5 GPa[4] (approximately 5,000 atm). At 77 K it can be recovered back to ambient pressure and kept indefinitely. At ambient pressure HDA has a density of 1.17 g/cm³[3].

    Very-high-density amorphous ice

    Very-high-density amorphous ice (VHDA), was discovered in 1996 by Mishima who observed that HDA became denser if warmed to 160 K at pressures between 1 and 2 GPa and has a density of 1.26 g/cm³ at ambient pressure [5]. More recently, workers at the University of Innsbruck have suggested that this denser amorphous ice was a third amorphous form of water, distinct from HDA, and called it VHDA [6]


  • Registered Users, Registered Users 2 Posts: 27,644 ✭✭✭✭nesf


    Ok, everyone seems to have lost the plot here (well, except Podge). The phase diagram for water looks as follows:

    water-phase-diagram.jpg

    Increasing pressure actually melts ice, as any ice-skater should be able to tell you. Yes, that is extremely unusual for a substance, but water behaves kind of odd. It happens for exactly the same reason water expands when it freezes. It doesn't matter how much pressure you apply, water is simply denser in it's liquid form, and so more pressure equals liquid. Unless you apply so much pressure you break apart the molecules or cause it to collapse into a neutron star or a black hole. Not something you'll achieve with a vice-grips, or even by dumping it on Jupiter.

    To add to this there has been some very interesting research done on super cooled water (i.e. liquid water at -200 degrees celcius and similar) by putting (a small) amount of water under incredible pressure and using liquid helium and similar as a coolant. The physical chemistry going on is fascinating.

    I'm sorry, I don't have any links, haven't seen any of this since I did a paper years back with a physics lecturer when I was a physics student. But if you search you should be able to find some cool stuff.


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  • Closed Accounts Posts: 125 ✭✭Azelfafage


    Dig Three Thosand miles under the surface of the earth.

    A block of granite 1 cubic meter..... on the surface.... willl shrink to a fraction of its surface size.

    1 cubic Meter of granite on the Surface becomes about 20 Cubic centimeters (or less)three thousand miles down under the desk you are sitting on.

    Of course Boyle's Law is an approximation...... but it applies to solids too.


    .


  • Registered Users, Registered Users 2 Posts: 7,792 ✭✭✭Mark Hamill


    Azelfafage wrote: »
    Dig Three Thosand miles under the surface of the earth.

    A block of granite 1 cubic meter..... on the surface.... willl shrink to a fraction of its surface size.

    1 cubic Meter of granite on the Surface becomes about 20 Cubic centimeters (or less)three thousand miles down under the desk you are sitting on.

    Of course Boyle's Law is an approximation...... but it applies to solids too.


    .

    Forget about the words solid liquid and gas. Boyles law applies to collections of molecules and says that the greater the pressure pushed on them, the lesser the volume they will occupy. The thing about water is that the most compressed form you make with water is the liquid form, as the solid form is a crystal latice stabilized by hydrogen bonding that is actually quite large. You are right in thinking that boyles law applies to liquid water, but almost all you get is denser liquid, not a solid as the intermolecular bonding required for solid water wont usually exist under the high pressure.


  • Registered Users, Registered Users 2 Posts: 237 ✭✭Moromaster


    Okay, thanks for the information.

    I recall reading somewhere that it is possible to solidify water by pressure but somehow it becomes endothermic, meaning it's colder then water :confused: I now understand that they were wrong. :P

    Why exactly doesn't it compress to ice? I don't understand this. :rolleyes:


  • Registered Users, Registered Users 2 Posts: 7,792 ✭✭✭Mark Hamill


    Moromaster wrote: »
    Okay, thanks for the information.

    I recall reading somewhere that it is possible to solidify water by pressure but somehow it becomes endothermic, meaning it's colder then water :confused: I now understand that they were wrong. :P

    Why exactly doesn't it compress to ice? I don't understand this. :rolleyes:

    I will try to explain this.
    Most compounds would be like lego. In the liquid form, they are like a big pile of lego,
    lego%20bricks.jpg,
    free movie and flowing around each other. When compressed into solid form, they make a well ordered structure,
    lego_rubiks_cube.jpg,
    that usually will take up less volume than the liquid form because the molecules, or lego pieces, can stack right next to one another and the orientation of one molecule relative to another isnt a big deal for stacking.
    Water molecules, on the other hand, are like pieces of knex:
    K%27nex%28Pieces-Small%29.jpg.
    They will stack, but due to hydrogen bonding, they can only stack in certain shapes (certain parts of one molecule want to be near to other certain parts of other molecules) and many gaps will appear:
    calculator_small-1.jpg,
    so the same amount of molecules of water will occupy a larger space when solid.
    As far as I can tell, high density ice is made by compressing regular ice, not water, so i would see that as taking the knex structure and twisting it at both ends while squeezing it, this will eliminate the gaps while keeping the hydrogen bonding happy.

    Hope that helps


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