Fluid Density Activity: Non-Sticky, Safe, and Cheap

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flatmaster
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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?
 
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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.
 
High school.student safe
 
Just as an example, I'm pretty sure a student tasted the corn syrup because it smelled "heavenly"
 
flatmaster said:
Just as an example, I'm pretty sure a student tasted the corn syrup because it smelled "heavenly"

Well by that standard even glycol is out (since it happens to taste sweet)!
Glycerine perhaps?
 
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.
 
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.
 
minerva said:
Lithium heteropolytungstate aqueous solution: 2.9 g/cm3; not significant toxic.

That sounds like an awesome drink, can I get one of those on the rocks with a little umbrella? :smile:
 
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.