DeIonized Plasma
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Solid sulfuric acid?
So I was looking at the wikipedia page on sulfuric acid and found this.
Has anyone ever made this supposed anhydrous pyrosulfuric acid?
Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.
~Marie Curie
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hissingnoise
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Disulphuric acid H2S2O7 is simply SO3 saturated oleum!
Being a solid @RT it has but few uses . . . ?
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Bert
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http://www.sciencemadness.org/talk/viewthread.php?tid=5495&a...
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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j_sum1
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I wouldn't touch it.
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plastics
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I would!
Here is some solid SO3
And the apparatus that generated it from sodium hydrogen sulphate. note white fumes issuing from drying tube
Just needs sensible precautions as always!
 
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j_sum1
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Ok plastics. You just earned your hazard to others badge!
100th post in classy fashion.
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Molecular Manipulations
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I've made it a couple times, decomposition of a metal sulfate was my method. Using an all glass apparatus and leading the sulfur trioxide into 98%
sulfuric acid worked fine, not easy, not practical.
-The manipulator
We are all here on earth to help others; what on earth the others are here for I don't know. -W. H. Auden
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Loptr
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Quote: Originally posted by Molecular Manipulations  | | I've made it a couple times, decomposition of a metal sulfate was my method. Using an all glass apparatus and leading the sulfur trioxide into 98%
sulfuric acid worked fine, not easy, not practical. |
What sort of temperatures are we talking about in order to decompose the metal sulfate? Also, how long does this reaction typically take?
Also, wouldn't you have issues with the glass breaking on cooling with the cake still inside?
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Molecular Manipulations
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I used a quartz tube the second time, and the metal being copper (II) sulfate, the required temperature is only around 550°C, although I used closer
to 600°C. I was impatient and didn't wait for the reaction to complete, got only 12% yield (by decomposed sulfate), which took about 30 minutes from
the time heat was added to when I turned off the Bunsen. The small quantity of 98% acid and turned to just over 110%, acc. to my acid titration. Which
I had calculated to be about 93-95% SO3 absorption (including potential sulfur (VI) reduction by the high temperatures).
The first time I hardly did any analysis of yields and thus have no data.
-The manipulator
We are all here on earth to help others; what on earth the others are here for I don't know. -W. H. Auden
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jock88
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See the thread in Republications
As per:
http://www.sciencemadness.org/talk/viewthread.php?tid=10332
http://www.sciencemadness.org/talk/viewthread.php?tid=10012
http://www.sciencemadness.org/talk/viewthread.php?tid=5495
[Edited on 18-6-2015 by jock88]
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