Nixie
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Looking for photo of supercritical water
What the title says. I didn't find anything with Google's image search.
\"Good is a product of the ethical and spiritual artistry of individuals; it cannot be mass-produced.\" --Aldous Huxley
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solo
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Here is a picture of the supercritical water...........source,
http://www.russia-ic.com/news/show/3414/
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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unionised
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The fact that some things turn supercritical was first noted with CO2 in a sealed glass tube. The interestingthing that people noticed was that, above
the critical temperature, the meniscus separating the 2 phases (liquid and gas) disapeared. Since that picture is of 2 distinct phases it can't be
supercritical water.
A tube containing supercritical water would look pretty much like one full of air.
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-jeffB
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Are you sure that's what you want? Supercritical water, water that's above (rather than near) its critical point, would just look like a
featureless fluid. And its critical point is so high that providing a viewing window becomes a challenge.
I did find a VIDEO here:
http://tanzanite.chem.psu.edu/demos.html
...but it's of water in a diamond anvil cell, and it's a little hard to interpret. There's also a SPECTACULAR video of CO<sub>2</sub> in
a tube. The movies are long and high-resolution -- the water video is 82MB (720x480, QuickTime format), and the CO<sub>2</sub> video is
366MB (869x480)!
Edit: okay, so I'm slow. I was waiting for that 366MB behemoth to finish coming down... 
[Edited on 1-12-08 by -jeffB]
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Nixie
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| Quote: | | Originally posted by unionisedThe interestingthing that people noticed was that, above the critical temperature, the meniscus separating the
2 phases (liquid and gas) disapeared. Since that picture is of 2 distinct phases it can't be supercritical water. |
There are indeed two phases in his photo, but there is no meniscus. Meniscus doesn't mean any general surface between liquid and gas such as the
bubbles in the photo, but refers to the specific curved surface that occurs in a narrow vessel due to surface tension and the liquid either wetting or
being repelled by the walls.
[Edited on 12-1-2008 by Nixie]
\"Good is a product of the ethical and spiritual artistry of individuals; it cannot be mass-produced.\" --Aldous Huxley
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chemoleo
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Also check out the supercritical transition of SF6, and the awesome disappearance of any meniscus and refractive effects of the liquid vs gas (low
res)
http://www.rsc.org/suppdata/jm/b3/b315262f%2De/
Also, here with CO2, where critical opalescence occurs:
http://www.rsc.org/suppdata/jm/b3/b315262f-b/
about critical opalescence:
http://en.wikipedia.org/wiki/Critical_opalescence
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12AX7
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Neato!
FWIW, for anyone who doesn't have (or hates) Quicktime, those videos are embedded MPEGs. View source, copy the link ("Clip2.MPEG" for the second one,
and I think it was "Clip5.MPEG" for the first) and paste onto the end of the URL. It will download/open in your default video viewer.
Tim
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Nixie
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Quicktime files can be viewed without Quicktime by installing the Quicktime Alternative codecs (same for Real -- Real Alternative)
\"Good is a product of the ethical and spiritual artistry of individuals; it cannot be mass-produced.\" --Aldous Huxley
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unionised
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"There are indeed two phases in his photo, but there is no meniscus. Meniscus doesn't mean any general surface between liquid and gas such as the
bubbles in the photo, but refers to the specific curved surface that occurs in a narrow vessel due to surface tension and the liquid either wetting or
being repelled by the walls."
So?
It's not like anyone said there was a meniscus and, for what it's worth the vessel doesn't need to be narrow and the interface between a liquid and
gas needn't be curved. BTW, I understand the same word is used for some bit of the knee too.
The point is that that picture doesn'tshow supercritical water which is what the OP asked for.
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chemoleo
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Well isn't a meniscus a direct result of molecular ordering to minimise the exposure of i.e. polarised charged groups to the other medium, here the
gas? I would have thought this sums it up nicely - under supercritical conditions, there is no more such ordering required, hence the 'meniscus' (or
the structured interface separating the two phases) dissipates and vanishes entirely.
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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