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    Why recrystallization works on the basis that cooled solution is saturated with the desired material but not with the impurities?

    Cuz I thought it is the desired material got crystallized, not the impurities?

    Did I misunderstand something?

    Thanks for any replies in advance
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    when you wash it through with a solvent, the desired product stays and the impurities dissolve with and you end up with the crystals and a bunch of solvent with the impurities dissolved in it.
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    (Original post by MrFartFace)
    when you wash it through with a solvent, the desired product stays and the impurities dissolve with and you end up with the crystals and a bunch of solvent with the impurities dissolved in it.
    This thread is about recrystallisation, not washing on a filter...
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    (Original post by MrFartFace)
    when you wash it through with a solvent, the desired product stays and the impurities dissolve with and you end up with the crystals and a bunch of solvent with the impurities dissolved in it.
    Then the solvent is saturated with impurities isn't it?
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    (Original post by mystreet091234)
    Then the solvent is saturated with impurities isn't it?
    The solvent has all the impurities dissolved in it, the crystals shouldn't dissolve in the solvent, they stay in the funnel.
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    (Original post by MrFartFace)
    The solvent has all the impurities dissolved in it, the crystals shouldn't dissolve in the solvent, they stay in the funnel.
    Have you ever done a recrystallisation? What you have said is completely wrong.
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    Yeah I did the PSA in it earlier this year.
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    (Original post by MrFartFace)
    Yeah I did the PSA in it earlier this year.
    Then you did it wrong. In a recryst you dissolve the crude product, filter out any insoluble impurities and cool the filtered solution to get your purified product, followed by drying.
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    (Original post by alow)
    Then you did it wrong. In a recryst you dissolve the crude product, filter out any insoluble impurities and cool the filtered solution to get your purified product, followed by drying.
    Cheers for clearing that up.
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    (Original post by MrFartFace)
    The solvent has all the impurities dissolved in it, the crystals shouldn't dissolve in the solvent, they stay in the funnel.
    Actually this is the question I was talking about.

    I think D is weird as the solution should be saturated with soluble impurities, though I know ABC must be wrong.
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    It's D, when you cool it, the purer product is formed, but the impurities stay mostly dissolved
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    (Original post by MrFartFace)
    It's D
    Yea I know
    But why?
 
 
 
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