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Why do we crystallise the product?

  1. Apr 16, 2007 #1
    Why do we crystallise the product??

    hehehehhe... why do we crystallise the product??..and why do we ethanol and water to crystallise them??

    im a physics student.

    but this chem question came accross me and i just wanna know to make things more clearer..

    i know this is an extremely easy question for chem student.... and even comonsense can figure it out..:mad: but... some how..i just dont see it.
  2. jcsd
  3. Apr 16, 2007 #2


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    We crystallize things to purify them.... and we like the crystals.
  4. Apr 16, 2007 #3
    it depends on what your compound is also. recrystallization is more of an art. you have to find the perfect solvent/solvent system that won't dissolve your product at room temperature, but will dissolve it when you heat it.

    recrystallization is used to purify your stuff like chemistree said. it is the absolute best way to purify things on an industrial sized scale. many process chemists will completely alter synthetic routes to come up with a way in which products can be recrystallized easily when things must be scaled up from a 500mg scale to a 5000 kg scale.

    on a small scale recrystallization is probably the least efficient way to purify something.
    Last edited: Apr 16, 2007
  5. Apr 16, 2007 #4


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    If you tell us what reaction or compound you're dealing with, someone might be able to help answer your question about why use ethanol and water. Otherwise, without knowing anything more about it, all you will get are the general answers about why crystallization is useful.
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