mewrox99
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Exotic Hypochlorites and Chlorites
What interesting hypochlorites can be synthesized. Sodium Hypochlorite and Calcium Hypochlorite are the only ionic hypochlorites I know off.
What about Lithium Hypochlorite, Copper Hypochlorite or even Silver Hypochlorite.
Can they exist at STP and are they any known proprieties about these compounds
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stygian
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afaik
LiOCl is available for spas and such.
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JohnWW
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I think I have heard of organic hypochlorite and chlorite(III) esters. They are liable to be explosive, and sensitive to detonation. Chlorate(V) and
perchlorate(VII) esters even more dangerously so.
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mewrox99
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Perchloric acid esters? Wow. Do they really exist.
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mnick12
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Yes they do!
I once synthesized a small amount of urea perchlorate and the perchlorate salt of hexamine. I do not have my notes with me but I could go look for
them later. If I remember correctly I synthesized the perchloric acid by the reaction of fuming nitric acid on a saturated sol of ammonium
perchlorate. Then I neutralized the sol with urea and hexamine. The urea perchlorate precipitated as almost clear flaky crystals which decomposed on
heating releasing various chlorine oxides and left no residue. When mixed with a small amount of organic materials the urea perchlorate combusted
rather quickly with a very bright flame, so my guess is it is very good oxidizer.
Now the hexamine perchlorate had a consistency similar to RDX. When heated with an open flame it burned about as quick as RDX but with a very bright
greenish-blue flame (it was burned on a copper sheet).
I did not preform any sensitivity tests or stability tests, but my guess is that urea perchlorate is quite a bit more stable than the hexamine
perchlorate.
Any way thats all for now, if you have any questions or want more info I can go dig up my notes.
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mewrox99
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Urea Perchlorate. That sounds fascinating.
Please show me your notes. I wanna make some.
Do you think I can make the HClO4 from NH4ClO4 and H2SO4
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woelen
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mnick12, you're not talking about perchlorate esters! You made perchlorate salts, which conceptually are not much different from ammonium perchlorate.
The amino-groups in your organic compounds simply are protonated and you get salts of that. In a similar way I made ethylene diamine perchloratge
[NH3CH3CH3NH3](ClO4)2, diethylamine perchlorate [(CH3CH2)2NH2]ClO4 and also some others. None of these is particularly sensitive and they only inflame
or deflagrate on strong heating.
A true ester of perchloric acid is EXTREMELY dangerous. An example is CH3CH2OClO3, ethyl perchlorate. This is not an analogue of ammonium perchlorate,
but a truly covalent compound, containing the perchlorate group.
Perchlorate ion is quite stable, due to resonance stabilisation, while covalent perchlorate lacks such stabilisation. For this reason dilute
perchloric acid (up to 70%) is surprisingly inert and the same is true for ionic perchlorate salts. On the other hand, pure perchloric acid and also
covalent derivatives of this are very dangerous.
A similar effect exists for many other anions. Nitrates also are fairly inert and are not easily reacted in aqueous solution or at low temperatures.
Covalent nitrates (e.g. concentrated nitric acid and true nitrate esters) are much more reactive.
I know of the existence of hypochlorite esters, such as CH3CH2OCl (ethyl hypochlorite), but these are very dangerous and even looking bad at them may
cause them to explode. Hypochlorites are the least stable of all oxo-halates, the stability of these goes up as follows: ClO(-) < ClO2(-) <
ClO3(-) < ClO4(-).
For the covalent acids the sequence is HOCl ~ HOClO < HOClO2 < HOClO3
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Taoiseach
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Anhydrous Sodium hypochlorite can be made but it is only stable at low temperatures. Its an explosive crystalline solid.
Sodium chlorite is not explosive AFAIK and it can be bought online as a 28% solution. Google for "Jim Humble MMS". It would be interesting to make
lead chlorite from it (should precipate from addition of any soluble lead salt). Lead chlorite is explosive and its mixture with sugar was once
proposed as an primary explosive. I think Fedorof mentions explosive ammines of copper chlorite.
What is generally noteworthy is the decrease in stability with decreasing number of oxygene atoms in these chlorine oxyacids. The perchlorate is the
most stable, with the 4 electronegative O atoms shielding the positively charged Cl and protecting it against reduction. Chlorates are less stable,
and chlorites even less with the fewer oxygenes shielding the chlorine atom. In the hypochlorites ion, the chlorine is so prone to reduction that most
of these salts decompose over the time at room temperature.
Ethyl hypochlorite has been described in another thread; its pretty easy to make from bleach and ethanol but very unstable and dangerous.
The perchlorates of urea, hexammine and ethylenediamine are quite stable compounds. It would be interesting (yet possibly dangerous) to see if the
chlorate, chlorite or even hypochlorite of these amines could be made.
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psychokinetic
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So in other words, JohnWW - the interesting ones 
“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found
the object of his search.
I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.”
-Tesla
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mnick12
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Oh my I did not realize that woelen thank you for pointing that out! Talk about major brain fart, I mean I just finished a school project on
esterification.
But is interesting you mention ethyl perchlorate as I think there was an old thread describing the raw power and instability of ethyl perchlorate. And
here it is http://www.sciencemadness.org/talk/viewthread.php?tid=1081 quite a scary chem it sounds like.
Taoiseach:
I may be able to synthesize the hypochlorite or chlorate salts of some of these compounds. Since hypochlorite can be bought easily, and I have a few
pounds of chlorate from my electrochemistry experiments. I also have some potassium bromate that I made which may be more stable that the chlorates.
But the problem I see is synthesizing the free acid in any concentration since the way I synthesized perchloric acid relied on the ammonium salt
reacting with nitric acid. There are however other routes, but I do not know the dangers associated with them. I am however open to ideas.
Oh and one more thing, I could not find my notes on hexamine perchlorate and the notes on urea perchlorate are far less extensive than I previously
thought. But my notes basically say I mixed a ml of RFNA with a gram of ammonium perchlorate. Then the color changed to a more greenish yellow, and
the mix became syrupy. Oh and a small correction urea perchlorate DID burn, but only in larger amounts with a white-ish flame.
Boy I need to take better notes.
I am open to suggestions
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woelen
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Making chloric acid and bromic acid is not that easy. If you have NaClO3, then you can use that to make the less soluble Ba(ClO3)2. Perform a double
recrystallization from water.
Then you dissolve the Ba(ClO3)2 in water and add a precisely determined stoichiometric amount of sulphuric acid. BaSO4 precipitates and chloric acid
remains in solution.
Making bromic acid is somewhat easier (but still quite a hassle), because Ba(BrO3)2 is only very sparingly soluble in cold water. Dissolve KBrO3 and
Ba(NO3)2 in boiling hot water in the correct stoichiometric ratio and use as little water as possible. On cooling down, fairly pure crystals of
Ba(BrO3)2 are formed. A single recrystallization from a small amount of boiling hot water gives very pure Ba(BrO3)2. From this you then can make
bromic acid with sulphuric acid.
You cannot obtain pure HClO3 and HBrO3. HClO3 can only be kept safely at concentrations up to 30%. Above 40% it quickly decomposes, but even above 30%
it already slowly decomposes when warm. HBrO3 can only be concentrated to around 50%, but only in the cold. At room temperature I would not go further
than 40% with HBrO3.
Concentrating the dilute acids is not that difficult. Just boil off the water. The acids are fully ionized and do not escape from the liquid, they
behave like dissolved salts. It is best to boil off the water at reduced pressure to allow concentrating the acid at lower than 100 C temperature.
@Taoiseach: Solid chlorite is stable, but only when some chloride is present as well. I purchased half a kilo of 80% NaClO2 from eBay, the other 20%
being NaCl. Commercial NaClO2, intended for water purification (and since recently also for making MMS) always contains not less than 15% of NaCl,
intentionally crystallized together with the NaClO2. This prevents further decomposition. Without this NaCl, the chlorite slowly disproportionates
into NaClO3 and NaCl and this process slows down and stops when the solid contains 15% or so of NaCl. For human consumption, this is not good, because
of the formation of NaClO3. Hence the intentional addition of NaCl to material, used for human consumption. This NaCl is not added as a solid, but the
NaClO2 is crystallized from aqueous solution, together with NaCl. Apparently, these two chemicals form mix-crystals.
[Edited on 10-6-10 by woelen]
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mewrox99
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I know I'm going of topic. But what about Periodate esters.
HMS-Beagle sells 5grams of solid Periodic Acid.
How stable are periodates compared with perchlorates
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franklyn
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The original thread on this _
http://www.sciencemadness.org/talk/viewthread.php?tid=1896
.
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woelen
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I do not know of any periodic esters, but salts of periodates are easy to make. I also have some periodic acid and from this I made some salts of
organisc amines and I also made ammonium periodate. These salts are stable and can be kept without problems. If you heat them, then they explode,
giving a purple cloud of iodine. Funny stuff, but nor more than that.
http://woelen.homescience.net/science/chem/exps/ammonium_per...
The webpage is about ammonium periodate, but I also tried salts of ethylene diamine and diethyl amine. These salts have similar properties, but they
also produce black soot on decomposition, besides the iodine.
Making periodic acid is not easy, but making periodate salts (either potassium or sodium salt) can be done easily, using standard chemicals only
(NaOH+NaI and chlorine or KOH+KI and chlorine).
http://woelen.homescience.net/science/chem/exps/KIO4_synth/i... (can also be done with KI instead of KIO3, adjust amounts accordingly)
http://woelen.homescience.net/science/chem/exps/Na2H3IO6/ind... (this is the variation with NaOH and NaI).
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mewrox99
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I'll buy some Periodic acid from HMS-Beagle sometime. Sounds like fun stuff to play with
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woelen
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I yesterday made some lead chlorite. This compound can easily be made at fairly good purity. I dissolved some sodium chlorite (80% NaClO2 + 20% NaCl
for making MMS solution, see above) in water and added an excess amount of a solution of lead nitrate. When this is done, then a dull-yellow
precipitate is formed, which fairly quickly settles at the bottom. This precipitate is mostly Pb(ClO2)2, but it almost certainly also contains PbCl2.
I rinsed the precipitate two time with water and then allowed it to dry at a warm dry place (appr. 40 C) for a day. This results in a yellow powder
(pale yellow with a greyish hue).
When the powder is heated, then it quickly decomposes, with a soft hissing noise, without visible flame and without leaving any residue. White smoke
is produced when it decomposes. If a somewhat larger amount (e.g. 100 mg) is put in a spoon and the spoon is heated from below, then it decomposes
with a soft puff.
A much more spectacular result is obtained if the lead chlorite is mixed with sulphur. For this purpose I took a small pile of lead chlorite and added
a similarly sized pile of sulphur powder (to the eye, no measurements of weights or volumes). I put both powders in a small dry beaker and swirled
this to mix the powders. I never scratched or pressed the mix! The result is a sulphur-yellow powder. When some of this is put on a miniature spatula
(a small pile of not more than 4x4 mm2 and not more than 4 mm height) and ignited, then it explodes with a grey/blue flame and a fairly strong bass
phump-sound. Not a sharp pitch, but a soft bass explosion. I was really surprised to see this behavior with just sulphur added to the mix, without
confinement. Ignition was very easy. The light output only is moderate, hence the naming of a grey flame, not a white flame.
I also tried a mix with magnalium 50/50, 400...800 mesh. When that is done, there is no explosion. It deflagrates with a very bright white flame and a
sharp hissing sound. Ignition is exceptionally easy, just keep it above a flame of a candle or an alcohol burner and it deflagrates.
Finally I tried a mix with red phosphorus. I simply added appr. equal volumes of powder of both chemicals to each other and swirled the mix. I only
mixed a few tens of mg. I did the mixing in an empty aluminium cup of a waxine candle (tea light) by simply swirling it. The resulting mix was coarse
and irregular, but I dared not scrape or press the chemicals to make the mix more uniform. When a pile of 4x4 mm2 and 3 mm height is taken from this
mix and kept near a flame, then an amazingly loud report is generated and burning droplets are ejected from the explosion over a distance of more than
50 cm! These droplets keep on burning for a few seconds. This latter effect is most likely due to the irregular mixing.
If you want to repeat this experiment, then be EXTREMELY careful and do not scale up. Do not mix more than a few tens of mg of Pb(ClO2) with red P or
sulphur. These mixes are amazingly powerful, particularly the mix with red P. Also avoid breating the smoke from these mixes. This smoke contains lead
salts and must be considered highly toxic.
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