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Dense non-sticky fluid

  1. Jun 18, 2010 #1
    I'm writing an activity on fluid density. I'm looking for a safe, cheap fluid denser than water to explore density. The idea is to replace messy corn syrup or honey. It's a pain to clean syrup fluids out of the manometer. Were already doing simulated sea water. Any ideas?
  2. jcsd
  3. Jun 18, 2010 #2


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    Hmm, how safe? How dense? When I think dense fluids with low viscosity, I mostly think of organic halides. E.g. chloroform and tet are both readily available and both have densities of about 1.5 kg/l, but they're also somewhat hazardous.

    Glycol is safer and cheaper, but less dense and stickier.
  4. Jun 18, 2010 #3
    High school.student safe
  5. Jun 18, 2010 #4
    Just as an example, I'm pretty sure a student tasted the corn syrup because it smelled "heavenly"
  6. Jun 18, 2010 #5


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    Well by that standard even glycol is out (since it happens to taste sweet)!
    Glycerine perhaps?
  7. Jun 18, 2010 #6
    Here are some interesting candidates for high-density solutions you might want to think about.

    It's not trivial to find common, cheap, easily obtainable high-density liquids which aren't at least somewhat toxic compounds.

    Dichloromethane: 1.33 g/cm3, slightly toxic.
    Chloroform: 1.48 g/cm3, moderately toxic.
    Carbon tetrachloride: 1.6 g/cm3; quite toxic.
    Zinc iodide in aqueous solution: density ?, not significantly toxic.
    Caesium formate aqueous solution: 2.3 g/cm3, not significantly toxic.
    Lithium heteropolytungstate aqueous solution: 2.9 g/cm3; not significant toxic.
    Bromoform: 2.9 g/cm3, slightly toxic.
    Tetrabromoethane: 3 g/cm3, slightly toxic.
    Diiodomethane: 3.33 g/cm3, moderately toxic.
    Clerici solution: 4.25 g/cm3, very toxic.
  8. Jun 18, 2010 #7
    Well, the overall activity is about sea water. I think I might model the current salinitu of the dead sea or the great salt lake. Besides, we already have a qualitative question about why one floats better in these bodies of water.
  9. Jun 18, 2010 #8


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    That sounds like an awesome drink, can I get one of those on the rocks with a little umbrella? :rofl:
  10. Jun 18, 2010 #9
    A water based solution of metal salts might work well:
    copper sulfate
    ferrous sulfate
    calcium carbonate
    some of these will be poisonous but that may help keep the gene pool in better shape.
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