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Author: Subject: Horribly Dangerous, but useful, Reaction
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[*] posted on 27-6-2010 at 15:15


Perhaps any HClO4 formed was immediately reacted as it formed...

Though, C2H2 dissolves in Methylbenzene. I dunno if that affects it but ah well.

See the other thread I posted in. There IS a double salt of Ag2C2:AgClO4 you know... And you do realize that in Ag2C2 synth via AgNO3 HNO3 is NOT formed so I cannot honestly see where the HClO4 can be formed...




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Anders Hoveland
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[*] posted on 27-6-2010 at 15:19


Quote: Originally posted by -=HeX=-  
And you do realize that in Ag2C2 synth via AgNO3 HNO3 is NOT formed ...


Really? What is the reaction?
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[*] posted on 27-6-2010 at 15:43


Huh, looks like I am wrong there as I honestly do not know... Is it really
C2H2 + 2AgNO3 => Ag2C2 + 2HNO3 then?
I never thought about it that way, but it may explain why low pH is optimal (hence acidifying the AgNO3 with HNO3...). Makes sense to me. Just never thought it through - figured the idea of HNO3 being formed was silly. So, in THEORY, starting with AgNO3, you COULD keep adding C22H2 indefinately, adding Ag powder to react with the formed HNO3 and keep forming more Ag2C2? Very interesting in theory anyways... And makes sense according to the theory!

However, theory and practice aint the same thing. I never was the best at theory because I always focussed on the practical 'glass juggling' and such. The only time theory was used was to work out HOW to do things OTC and so on.

But anyways, according to the theory, could you not simply do the following: AgClO4 in H2O (saturated soln.) acidified to very low pH with HClO4, bubble the C2H2 through, pray to the gods that you don't become one crispy critter, filter off the ppt of Ag2C2 when it stops forming and retain the supernatant fluid which you then dehydrate with P2O5 and distill or something? Surely safer than adding organic liquids to one of the more potent oxidizers! At the very least the organics would react to form perchlorates which have a tendency to blow up or decompose at random... Like the Pentaerythritol Tetraperchlorate we extracted* liked to 'annihilate' itself at the gentlest stimulus once dry.

*Once the esterification was completed, we diluted with 70% HClO4, then 50%, then 20% and finally water. This slow introduction of water prevented any explosions. The 10ml initial volume of the reaction was diluted to 2.5 litres, about 100ml Diethyl Ether added and the mix shaken violently and remotely, then separated using a sep. Funnel until most of the inorganic layer had passed through. The last bits of the inorganic layer were removed with great care using a pipette before 3/4 of the Ether was evaporated, Na2CO3 was added in soln. the mix shaken again, more DiEthyl Ether added, the mix separated, and then the organic layer left to evaporate. Approx 350mg of a white crystalline ppt. was collected, only 10mg of which made it to tests, wherin a sample was ignited and it exploded violently. The remaining sample was halved. One half exploded for some strange reason, possibly a shock or something, the other half just 'vanished' leaving some inert residue shit behind.




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[*] posted on 1-7-2010 at 21:34


You should have seen when I reacted Cl2O7 with urea. Apparently the NHClO3 group is not particularly stable,even in an icebath, and that is an understatement.

"C2H2 + 2AgNO3 => Ag2C2 + 2HNO3 then?"

Yes, but if the HNO3 becomes too concentrated it will react with the Ag2C2 that is forming. I wonder if I might get some silver fulminate this way?
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[*] posted on 4-7-2010 at 14:14


Silver fulminate as a byproduct? scary proposition man. I find the THOUGHT of that stuff horrifying.

Cl2O7 and urea sounds fun... Try a dry ice-acetone bath...




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[*] posted on 9-7-2010 at 10:44


"Cl2O7 is soluble in benzene, slowly attacking the solvent with water to form perchloric acid" this quote is from another post. I wonder if, perhaps a trace of water is required to catalyze the reaction of Cl2O7 with benzene. Perhaps HClO4 is more reactive with benzene than the anhydride. And as benzene gets oxidized by HClO4, it just makes more water that reacts with Cl2O7 to make more HClO4. Cl2O7 might be somewhat sterically hindered, making it a less reactive oxidizer. Or perhaps there is some tiny equilibrium of the benzene being protonated (I think I read about this in superacid chemistry), and it is through the protonated product that a perchlorate ion can react ?
So theoretically, absolutely pure Cl2O7 might not react with benzene, but even one molecule of HClO4 would eventually lead to a chain reaction.
Cl2O7 is not entirely thermally stable, it slowly decomposes after several days, perhaps the intermediate radicals attack the benzene.



[Edited on 9-7-2010 by Anders Hoveland]
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