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Homework Help: Chemistry Question

  1. Feb 5, 2005 #1


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    i have this practical experiment coming up.
    i need any help available.
    i need to separate sand, salt, water through whatever means necassary.
    Thanks in advance.
  2. jcsd
  3. Feb 5, 2005 #2
    Hmm how about first heat the mixture so salt will dissolve but sand will not then filter the sand out. Then cool the water near 0, which decreases the solubility of salt in water. Then you can filter the salt too.
  4. Feb 5, 2005 #3


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    i don't understand how sand will not filter out sand. And when water is near 0, how are you going to filter it out, it's ice!!!
  5. Feb 5, 2005 #4


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    This makes no sense. The sand will be less soluble in the water than the salt, so if the sand is not dissolved, you will be able to filter it out.

    No, it's not. Pure water freezes AT 0 degrees Celcius, (at atmospheric pressure) not NEAR. With added salt, the melting point is dropped even further, this is why we grit our roads.

    In any case, to separate water from salt, you should probably just boil the water off (obviously once you've removed your sand by filtration).
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