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How can you make ice sink ?

  1. Mar 23, 2008 #1
    How can you make ice "sink"?

    Is there a way to attach water molecules in a fashion that in their frozen state, they would be denser than liquid and sink in water instead of float? Or is there some substance you could mix with it to create this effect, preferably an edible substance?

    I think it would be awesome to drink from a cup where the ice is at the bottom. I hate sipping or not being able to drink fast because the ice is in my way! I have even thought about making a wire mesh that traps the ice at the bottom of a cup.
     
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  3. Mar 23, 2008 #2

    mrjeffy321

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    Ice is more efficient at cooling the liquid if it is floating at the top of the water, rather than at the bottom (since the cold water sinks and the warm water rising, convection currents develop to help the mixing).

    Ice made with heavy-water will sink in normal water.
    Heavy water is water made with Deuterium, a special type (isotope) of Hydrogen which has a nucleus containing 1 proton and 1 neutron (instead of just a single proton).
    I think that drinking heavy water is bad (in excess of a certain amount) for you since it takes your body more energy to process it than it does normal water (differences in density, heat capacity, and what-not), so this really isn’t much of a solution.
     
  4. Mar 23, 2008 #3
    What about cooling glass cubes?
     
  5. Mar 23, 2008 #4

    mrjeffy321

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    Both water and ice’s density will change with temperature.
    As you increase the temperature of the water its density decreases; at 100 °C (and 1 bar) it has a density of about .95840 g/cm^3.
    As you decrease the temperature of ice, its density had an upward trend (from the numbers I am looking at). At -180 °C, ice has a density of about .9340 g/cm^3.

    Even under these conditions (100 °C water, -180 °C ice), the ice is still less dense and will float). But ice has an upward, slowly, trending density, so it may be possible to continue cooling it to a point where its density is sufficiently high so as to sink in boiling water, or it may reach / approach a maximum density before that even happens.

    *Density values from CRC Handbook of Chemistry and Physics
     
  6. Mar 23, 2008 #5
    one could add something to the ice of course. given its density 0.9167 (wiki) you need to increase it by 9.1% which could be done by solving more than 9,1 g of something solid per 100 g of water. It really depends on your drink what substance you can contaminate it with.

    Or you could try freezing some juice or like that. depends on what you're drinking.

    or lets make ice cubes with a piece of metal in it and put a magnet under the cup. (Now that's hi-tech drinking !)
    As you mentioned a wire mesh, that could be held in place with a magnet. Wonder if that means redesigning the cup.

    hmm.. maybe you could just put a wire mesh on the top to keep the ice from getting into the mouth, if that is, i assume, what's bothering you
     
  7. Mar 23, 2008 #6
    You DON'T want to drink heavy water. It will kill you. It interferes will all of the hydrogen boding in your body,disrupts protein synthesis, and messes up DNA replication/transcription.
     
  8. Mar 23, 2008 #7

    TMM

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    You need to drink a very large amount for it to have a noticeable effect on you. The source I'm using for this is wikipedia though, so take this comment with a grain of salt.
     
  9. Mar 23, 2008 #8

    DaveC426913

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    Last edited: Mar 23, 2008
  10. Mar 24, 2008 #9
    Last edited: Mar 24, 2008
  11. Mar 24, 2008 #10

    DaveC426913

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    This actually happens to me quite often. I put the ice in my empty glass and let it sit (usually wihle I carry it and my can of pop out to my chair) for several minutes. By the time I'm ready to pour, the ice cubes have fused into a single mass and are jammed in the bottom of the glass even when I pour my pop in.

    So, one solution for you might be to use a glass that has an hourglass shape, and put your ice in before your drink. Then pour a tiny bit of your drink in - just enough to wet the cubes. They'll re-freeze as a solid mass.
     
  12. Mar 24, 2008 #11

    Gokul43201

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    There's a solution if you are willing to start drinking out of a Klein bottle.
     
  13. Mar 24, 2008 #12
    Wonder if anybody's ever tried to collect enough tritium and freeze it...
     
  14. Mar 24, 2008 #13
    But not in the ice, because the salt will not let it freeze. Unless your freezer is set very cold. ;)
     
  15. Mar 24, 2008 #14

    Moonbear

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    You could always use a straw so you're drinking from the part where the ice isn't. :biggrin:

    I don't think I've tried dunking any of those blue ice thingies in water to see what they do. There are other reusable "ice cubes" that are basically that blue ice stuff in amusing plastic shapes...the plastic keeps the bad stuff out of your drink...obviously don't use them if they are in any way damaged.
     
  16. Mar 24, 2008 #15

    DaveC426913

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    Just avoid the freezie mugs. They leak. I can't tell you how many times I've finished a drink only to find the glycol gone.
     
  17. Mar 24, 2008 #16

    Moonbear

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    Slow learner? I think I'd have done that ONCE and stopped using those mugs. :wink:
     
  18. Mar 24, 2008 #17
    One can get the ice to sink in water, if you blow air into the glass. The air bubbles will lower the density of the continuous phase, so the same ice density becomes too heavy to float. The continuous phase is the average density of air and water, which can drop below the 0.9 gm/cm of ice.
     
  19. Mar 26, 2008 #18




    I Like the way you think! This seems my most resonable solution. I am have chronic dehydration problems and am very thirsty, don't think drinking out of a straw will cut it. Except the straws they give you at panera bread, which are like three times the diameter of a normal restaurant straw!


    I guess I will always keep this in mind too:

    [​IMG]
     
  20. Mar 26, 2008 #19

    DaveC426913

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    Have you ever been tested for Diabetes?
     
  21. Apr 9, 2008 #20
    Use a glass made of ice and have the liquid in that glass. Youv find tools to make ice-shot-glasses etc on the net.. ;>

    They also have some kind of false acrylic icequbes who flashes with leds as they come in contact with water.
     
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