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What should I do with silicon?

  1. Apr 5, 2016 #1

    Theoden

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    Let's say I have an amount of freshly-isolated silicon in the bottom of a jar of water. I have heard it is usable for water filtration; but how else could I use this element, and with it could I make silicone? I have searched google on making silicone, but all I have found are subjects about things like caulking.
    Any help would be greatly appreciated!
     
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  3. Apr 5, 2016 #2

    ProfuselyQuarky

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    Is this just for jun? A project or experiment?
     
  4. Apr 5, 2016 #3

    Theoden

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    I suppose this would be an experiment.
     
  5. Apr 5, 2016 #4

    mfb

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    So you just have some piece of silicon (is it really pure silicon, or silicon oxide, doped or something else?) and you don't know what to do with it?

    You could check if it really behaves like a semiconductor, e. g. decreases its resistance when heated.
     
  6. Apr 5, 2016 #5

    ProfuselyQuarky

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    That's a good one. I was going to say that, but you beat me to it :)

    I would also say build yourself a solar cell, but that's not plausible.
     
  7. Apr 5, 2016 #6

    SteamKing

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    Well, sand (SiO2) is used in water filtration commonly, but I've never heard of elemental silicon being used in that fashion.
     
  8. Apr 5, 2016 #7

    TeethWhitener

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    Are you sure you mean to say silicon and not silica? How exactly do you precipitate elemental silicon in water?
     
  9. Apr 6, 2016 #8

    Theoden

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    Thanks everyone!

    The isolation recipe involves mixing silica with magnesium and heating it ( to separate it into layers: magnesium, magnesium oxide, magnesium silicide, and purified silicon at the bottom ), then dropping it in in a diluted form of muriatic acid ( to get everything but the purified silicon out of the solution ). The skeleton equations would be something like this:
    12Mg + HCl --> 12Mg + H + Cl
    Si + HCI --> SiH4 + Cl
     
  10. Apr 6, 2016 #9

    TeethWhitener

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    1) Heating magnesium metal and working with silane gas are both very dangerous propositions, even for someone who knows what they're doing (see point 2).
    2) Your equations make no sense. "H" and "Cl" by themselves are not species that appear in chemical reactions like this. Also, combining magnesium with HCl will give you hydrogen gas and MgCl2. Combining silicon with HCl will probably give you silicon tetrachloride, or at best a mixed silicon hydrochloride.
    3) Even if you do manage to prepare silane gas, it is immediately pyrophoric (catches fire spontaneously) in air.

    I think what you're trying to do here is to thermally decompose silane derived from magnesium silicide. Given the level of chemistry knowledge demonstrated in your other posts on this thread, I can't in good conscience recommend you do this on your own.
     
  11. Apr 6, 2016 #10

    Theoden

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    I'd have to admit, this process is very dangerous; and must be done under a fume hood, perhaps with a gas mask, and possibly behind a blast sheild. Thank you for your concern! I will continue to take precautions when preforming. I personally think the production of silane gas is the most interesting aspect of the process; but I agree, It should also be done outside or in a fume hood.
    I did not know magnesium and chlorine combined. Thanks for pointing that out! I knew something was wrong with my equation, but I couldn't figure the problem out until you mentioned it.
    I assume this would be the fixed version:
    12Mg + HCl --> MgCl2 + H

    Thanks again!
     
  12. Apr 6, 2016 #11

    mfb

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    It is dangerous even if you do it with all those precautions. And where is the point? You don't have the knowledge to do it safely, and we won't help to hurt yourself here. Thread closed.
     
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