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Formatik
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[*] posted on 6-5-2011 at 20:15


I also didn't see any flames when dripping chromyl chloride onto sulfur flowers, back when I made the chloride by distilling it out of a retort. The reaction did sizzle and released gas.

I was trying to extract N-methylpyrrolidone from paint stripper, but during heating the thermometer broke and ruined the extraction, since it left me with a contaminated liquid. The contaminated liquid didn't react with KMnO4, which I didn't pulverize either. I don't think this tells anything about reaction between N-methylpyrrolidone and KMnO4.

Woelen, if you've still got periodic acid, you could react it with DMSO and see if it does anything. It may react violently. Too violent for ignition though (article below).

[Edited on 7-5-2011 by Formatik]

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[*] posted on 7-5-2011 at 11:37


I tried the LiAlH4 mixes with KClO4, KClO3 and NaClO2. Given the extremely reactive nature of LiAlH4 I expected these mixes to be insanely unstable and very easy to ignite, simply by adding some water. This has proven not to be the case.

All of these mixes can easily be ignited by means of a flame. The mix with KClO4 burns very fast with a white flame (like Mg fire), showing many sparks. The mix with KClO3 burns in a similar way, but the color of the flame is somewhat colored, slightly red/pink. The mix with NaClO2 is by far the most energetic. It burns VERY fast, a single whoosh and a fuzzy deep orange fireball is produced and then it is gone. I would say that this is near-explosion.

I also made some KClO3/LiAlH4 mix and did a test by hitting it with a metal rod. I could not manage to ignite the mix in this way. I increased the force, but dared not go further, being afraid that I would ram my watch glass into pieces. E.g. a mix of KClO3 and red P only needs a gentle tap of a glass rod to get it going. I did the same test with NaClO2/LiAlH4 mix. I even did a test by adding a tiny drop of 30% HCl to this mix. This gives a lot of sizzling and a yellow cloud of ClO2 is formed, but the dry part of the mix does not ignite.

So, apparently LiAlH4 is less sensitive than I expected. Only when this material comes into contact with water in larger quantities, then it can ignite and give rise to fire.

LiAlH4 without any oxidizer mixed in burns with a lovely red flame.

I'll try to make videos of the burning of these mixes and post them here. These video's have to be made in daylight, otherwise the camera's CCD will be totally overexposed. It does not adjust quickly enough to the large light output of the burning of these mixes.

Most impressive though is the burning of the NaClO2/LiAlH4 mix. It is VERY violent and if a somewhat larger amount is taken, I can imagine that a real explosion with corresponding report is obtained, even with unconfined powder. I myself do not feel confident however of handling more than 100 mg amounts of these mixes. I do not want an accident. Even just 1 gram of a mix can give a nasty accident if it sets of unexpectedly.

[Edited on 7-5-11 by woelen]




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[*] posted on 8-5-2011 at 04:16


i'will soon get perchloric acid 65-70%, i'm going to mix it with some organic compounds and i'll se what happens!
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[*] posted on 8-5-2011 at 04:18


Surprisingly not too much with 70% stuff. Having said that an explosion can still occur with organics so be extremely careful
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[*] posted on 8-5-2011 at 04:20


i'will soon get perchloric acid 65-70%, i'm going to mix it with some organic compounds and i'll se what happens!
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[*] posted on 8-5-2011 at 05:19


Don't expect anything spectacular with that acid. Some reactions can be exothermic (e.g. reaction with NH3 or an organic amine), but these are merely acid-base reaction. A truly exothermic redox reaction which can show fire and/or explosion requires anhydrous HClO4 or strong heating of the mixture.

----------------------------------------------------------------------

I have done an experiment with periodic acid and 64% hydrazine. This liqud fumes in contact with air, albeit not strongly. When solid periodic acid is added to some of this liquid then a smooth and slowly accelerating reaction occurs. White smoke is produced. The reaction was much less violent than I expected it to be.

Next, I prepared appr. 30% hydrazine and added some solid periodic acid to this. When this is done with pea-sized pieces of periodic acid, then small explosions occur, and the pieces of periodic acid are launched from the liquid. If smaller particles of periodic acid are used, then no explosions occur, but a plume of iodine and some yellow compound is produced.

The 30% solution reacts more violently than the 64% solution. This might be because of better solubility of periodic acid in such a more dilute solution. A similar effect I have observed before in other reactions, e.g. anhydrous sodium carbonate dissolves more vigorously in 10% HCl than in 35% HCl.

I made some videos of these reactions. The first video is of the reaction with 64% hydrazine:
http://www.homescience.net/chem/exps/hydrazine_periodate/n2h...

The next two videos are with 30% hydrazine. The difference between the videos is the use of background. In the last video you also can nicely see how the piece of periodic acid jumps up after a small explosion.

http://www.homescience.net/chem/exps/hydrazine_periodate/n2h...
http://www.homescience.net/chem/exps/hydrazine_periodate/n2h...

The grey clouds in the last video are no real clouds. These are shadows from the real smoke.

[Edited on 8-5-11 by woelen]




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[*] posted on 8-5-2011 at 06:52


Quote: Originally posted by woelen  
Don't expect anything spectacular with that acid. Some reactions can be exothermic (e.g. reaction with NH3 or an organic amine), but these are merely acid-base reaction. A truly exothermic redox reaction which can show fire and/or explosion requires anhydrous HClO4 or strong heating of the mixture.

[Edited on 8-5-11 by woelen]

I've read that at a concentration >70% explodes very easily.
If doesn't make any interesting reaction, I'll make some perchlorates and use them.
I'm going to do also some experiments with sodium chlorite(technical grade)
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[*] posted on 8-5-2011 at 07:07


Perchloric acid is completely ionized up to a concentration of 72%. Above that concentration, there will be covalently bound HClO4 (albeit still hydrated). Only the latter is extremely reactive.

You can make a more reactive acid by mixing the 70% acid with concentrated sulphuric acid. The sulphuric acid will take up most of the water and the HClO4 will be present as non-ionized molecule.

Boiling down the acid does not work. At around 200 C (I don't remember the exact temperature), the azeotrope boils over. This is acid at just over 70%.

Pure HClO4 is unstable and slowly decomposes, giving oxides of chlorine, oxygen and chlorine. Pure HClO4 slowly turns dark on storage and such a dark acid is unstable and may explode without clear reason.

I myself have 60% HClO4 and have done quite a few experiments with that. I have boiled it with many reductors, driving off quite some water and increasing the concentration to nearly 70%, but no reaction occurred. Even fairly strong reductors like sulfite and iodide are not oxidized by boiling with 60+ % HClO4.

It is interesting though to make some perchlorate salts from the acid (e.g. from amines, hydrazine). These salts are stable at room temperature but are quite energetic when strongly heated.




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[*] posted on 8-5-2011 at 07:54


Yes, I think that I'll make triethylammonium perchlorate from this acid.
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[*] posted on 8-5-2011 at 20:24


i love the compounds that start fire with water
negative X - ammonium chloride ammonium nitrate and zinc and water
sodium peroxide and cotton and water
potassium ferrate and ethylene glycol I've heard of someone doing this one i wish to try
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[*] posted on 8-5-2011 at 23:31


Intriguing results, woelen.

The fuming nature of hydrazine hydrate is such, that one might not see fumes after opening the container until after it was exposed to atmospheric air for some time. I've also noticed pressure build-up in the little brown glass container I stored it in.

Conc. HClO4 reacts vigorously with almost nothing, except maybe sulfoxides. I've described reaction with DMSO in my hypergolics thread. Vigorous decomposition has been claimed to occur with ketones, glycols, and glycol ethers. But many organics it's mixed with turns into a high explosive of often questionable stability or even high sensitivity.

Another reaction: Turpentine dumped into a mixture of red fuming nitric acid containing 10% KMnO4:

burningturpentine.png - 556kB
http://www.megaupload.com/?d=3ED9MGA4

The reaction makes a lot of soot. KMnO4 is needed for the reaction. Ethanol catches fire right away with the same acid having even 2.5% KMnO4, but the flame is hard to see in the daylight and reaction not as impressive.

[Edited on 9-5-2011 by Formatik]
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[*] posted on 9-5-2011 at 12:55


I can't watch the videos :(
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[*] posted on 9-5-2011 at 13:59


Try using an American server.

[Edited on 9-5-2011 by Formatik]
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[*] posted on 9-5-2011 at 22:36


I to get the message

<b>The file you are trying to access is temporarily unavailable. Please try again later</b>
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[*] posted on 10-5-2011 at 04:53


Quote: Originally posted by mewrox99  
I to get the message

<b>The file you are trying to access is temporarily unavailable. Please try again later</b>

Me too!
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[*] posted on 10-5-2011 at 10:50


I got the message once too, but reloaded the page a few times and it works.
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[*] posted on 29-5-2011 at 12:33


I contribute a new movie to the fire project. The self-ignition of red phosphorus when sprinkled on solid periodic acid:




Here is a link to the webpage:
http://woelen.homescience.net/science/chem/exps/H5IO6_P/inde...

The webpage contains a video. You may download this from the webpage and use that in the Youtube channel on making fire.








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[*] posted on 29-5-2011 at 12:36


Very cool woelen! Seeing as NurdRage vowed to not return to this thready did you U2U it to him?

On a related note, what is the easiest way to make periodic acid? I can make potassium periodate, could I recrystalize with HCl?




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[*] posted on 29-5-2011 at 13:22


Quote: Originally posted by Formatik  


Conc. HClO4 reacts vigorously with almost nothing, except maybe sulfoxides.


Almost noting is a little strong, however, withing the limits
of what is being discussed here you dobe correct.

For your edification and amusement.

NB - GF Smith has gotten antsy - unless you are a business or
educational institution - you probable are not going to be
able to get them to supply you with a free copy of the two pubs I mention.


Perchloric Acid and Perchlorates
Alfred A Schilt
([is/was] Free on application from - GF Smith Chemical Co 1979

[Also free (was) G F Smith The Wet Chemical Oxidation
of Organic Compositions Employing Perchloric Acid
with — or — without added HNO3 - H5IO6 – H2SO4 ]


ANHYDROUS PERCHLORIC ACID

Preparation and Properties

The preparation of anhydrous perchloric acid can be readily
achieved by fractional distillation of a mixture of concentrated
sulfuric acid and 65-70% perchloric acid 94,95 Magnesium
perchlorate, 96 phosphorous pentoxide, 97 and Sulfur 97 have also
been described as dehydration agents in place of sulfuric acid.
Anhydrous perchloric acid can also be obtained by extration into
methylene chloride from a mixture of one part by volume of 70%
perchloric acid and four parts 25% fuming sulfuric acid. 88 It
has been recommended that only small amounts of reagents be used
in this procedure and that the extraction flask be kept cold
because of the risk of an explosion.98 Procedures for the
preparation of anhydrous [sic] deuterium Perchlorate and D3OC 104
have been described by Smith and Diehl.99

The anhydrous acid is colorless, hygroscopic, volatile, extremely
reactive, and explosively unstable. In contact with skin it
produces serious and painful wounds. On addition to water it
generates considerable heat and a hissing noise. It freezes at
—112o and boils at 18 mm at 16o without decomposition. It can not
be distilled at ordinary pressures without decomposition and
explodes at about 90o. On standing at ordinary temperatures the
pure acid gradually yellows and eventually (within 10 to 30 days)
explodes spontaneously. Storage time can be extended up to 60
days by use of liquid-air temperatures without formation of
colored decomposition products. Extreme caution is necessary to
avoid contacting the anhydrous acid with wood, paper, or other
combustible matter because explosions invariably result, even at
ordinary temperatures. Except for special use or need anhydrous
perchloric acid should not be made or stored.

Anhydrous perchloric acid undergoes partial autodissociation to
chlorine heptoxide and oxonium perchlorate above its melting
point, and the rate of attainment of equilibrium increases
rapidly above –30o.100 The existence of the equilibrium 3 HCIO4
<-->Cl2O7 + HClO4 . H2O has been demonstrated from viscosity, 101
kinetics of decomposition and vapor pressure, 102 and electrical
measurements. 103 Rosolovskii 112 reports values for the
equilibrium constant (as written above) of 0.80 x 10-4 at –10o,
1.30 x 10-4 at 20o, and 1.94 x 10-4 at 70o. Bout and Potier103
report a value of 0.60 x 10-6 for the self -dissociation
equilibrium constant of the following reaction:

3 HClO4 <—-> ClO2O7 + H3O+ + ClO4-

This value differs from Rosolovskii's because of the difference
in formulating the oxonium perchlorate product. The extent of
self -dissociation is thus indicated in either formulation at
approximately 1 per cent.

Heat capacities and thermodynamic functions for anhydrous
perchloric acid from 5 to 55oK indicate that HClO4 exists as an
independent species in the crystalline state.104 At 298.15 oK its
heat capacity, Cp, is 28.80 cal/mol degree. A triple point occurs
at 172.0 oK.

Raman and infrared spectra of anhydrous HClO4 and DClO4 have been
extensively studied for all three physical states.105-7 There is
no evidence of any molecular association in the liquid state.
Bond energies, bond lengths, and standard thermodynamic
quantities have been estimated from the data.105

The thermal decomposition of anhydrous perchloric acid has been
studied extensively.108-116 Proceeding through the formation Of
Cl207, the following decomposition products are formed at 60-80o;
O2, HClO4.H20, ClO2, and Cl2.110 At 200-439o the products are
Cl2, H2O, and O2.110 In addition to Cl2 O7 other probable
intermediates include ClO3 and ClO4. At 10 mm and 300-400o, the
decomposition is first order with respect to HClO4. Catalysts, in
order of their activity, are Co2O3 > MnO2 > CuO > Fe2O3 > CuCr2O4
> Al2O3 > SiO2. 116

Reactions

An extremely powerful oxidant, anhydrous perchloric acid causes
explosions upon contact with most organic substances. It can,
however, be dissolved in chloroform, methylene chloride, acetic
acid, and certain other organic solvents for somewhat safer
employment in chemical reactions and syntheses. On dissolving it
in acetonitrile, it interacts with the solvent by H-bonding
initially and then very slowly transfers its proton to the
acetonitrile.117 Applications of the anhydrous acid in various
organic solvents have been reviewed by Burton and Praill.118

Neither hydrogen chloride nor hydrogen bromide react with
anhydrous perchloric acid but hydrogen iodide as well as sodium
iodide ignite on contact with it. Thionyl chloride also ignites
on contact but not sulfuryl chloride. Phosphorous oxychloride
dissolves it without reaction, while phosphorous pentachloride
reacts to give chlorine heptoxide. A solution of the acid in
chloroform explodes violently if poured upon phosphorous
pentoxide. Reaction with iodine yields deliquescent needles of
HIO3 [I2 3 [sic] Which when warmed give off iodine and leave
iodic acid as a residue.

Graphite reacts slowly with the anhydrous acid at room
temperature to give C24.9 ClO4 and ClO3.119 However, a drop added
to wood charcoal produces a violent explosion. Paper and wood are
ignited by the acid. The gas-phase reaction of perchloric acid
with hydrogen is first order in either reactant and yields
hydrogen chloride.120 Methane or ammonia is without effect on the
gas-phase reaction with hydrogen. 121 In the gas-phase reaction
of perchloric acid with ethylene the major products are HCI, CO,
and H2O; some 1,2-dichloroethane and vinyl chloride is also
produced together with minor amounts of numerous other organic
compounds, including C3 and C4 halides.122

PERCHLORIC ANHYDRIDE

Chlorine heptoxide, the anhydride of perchloric acid,. was first
isolated by Michael and Conn" by adding anhydrous perchloric acid
very slowly to phosphorous pentoxide cooled to –10o, and after
one day at –10o, distilling the product from the mixture at 82o.
They carefully reported that "the apparatus may be virtually
pulverized by violent explosion, and personal precautions must be
taken accordingly." More recently, Kolarov et al.123 described a
method which involves heating a mixture of anhydrous magnesium
Perchlorate with phosphorous pentoxide in a ratio of 1 to 1-2 at
100-160o and 1-2 mm for 2-5 hours to obtain a pale
yellow-to-orange product as distillate collected in a receiver
cooled to –78o. The distillate is free of phosphoric acid but
contains lower oxides of chlorine. Use of hydrated magnesium
Perchlorate led to an explosion. Replacement of magnesium
Perchlorate with potassium or ammonium Perchlorate gave no
product.

Chlorine heptoxide. Cl2O7, is a colorless volatile oil which
decomposes spontaneously on standing for a few days, turning
greenish-yellow. According to Babaeva,121 only 33.5% decomposed
in 502 min. at 80o. In the presence of 1% HClO4 the rate of
oxygen evolution is increased and the final product is oxonium
perchlorate.

Perchloric anhydride is soluble in and slowly attacks benzene,
reacts slowly with water to form perchloric acid, reacts with
iodine to form iodine pentoxide, and explodes on contact with
flame or by percussion. It volatilizes rapidly, so that a small
amount dropped onto paper or wood may evaporate before it can
react violently. Reaction with olefins yields impact- sensitive
alykl perchlorates.125 It is soluble in phosphorous oxychloride,
producing normal freezing point lowering indicative of the
molecular state
Cl2 O7.126


88. F. Klages and P. Hegenberg, Angew, Chem., 74, 902 (1962).
120. P. W. M. Jacobs and J. Stevenson, Combust. Flume, 19, 343
(1972).
94. G. F. Smith, J. Amer. Chem. Soc 75, 184 (1953).
95. G. Mascherpa, Compt. Rend., 252, 1800 .1961).
96. G. F. Smith. Talanta, 7, 212 (1961).
97. A. A. Zinov'ev, Zhur. Neorg. Kliho., 3,1205 (1958).
98. H. Musso and B. Bock, Angew, Chem., Int. Ed. Engl., 9, 75
(1970).
99. G. F. Smith and H. Diehl, Anal. Cheim, Proc. Intern, Symp..
Birininghom Univ., Birmingham, Engl. 1962, 394.
100. A. 1. Karelia, Z. I. Gregorovich, and V. Ya. Rosolovskii,
Izv. Akad. Nauk. SSSR, Ser. Khim. (3), 665 (1975),
101. A. A. Zinov'ev and V. Y. Rosolovskii, Zhur. Neoig. Khim., 5,
2564
(1960).
102. V. Y. Rusolovskii, Zhur. Neorg. Khirn., 11, 2161 (1966).
103. N. Bout and J. Potier, Rev. Chim. Miner., 4,621 (1967).
104. J. C. Trowbridge and E. F. Westrum, Jr., J. Phys. Chem., 68,
42 (1964).
105. P. A. Giguere and R Savoie, Con. J. Chem., 40,495 (1961).
106. A. 1. Karelia, Z. 1. Grigorovich, and V. Ya. Rosolovskii,
Spectrachim. Acto, Part A, 31A, 765 (1975).
107. A. 1. Karelia and Z. 1. Grigorovich. Spectrochim. Acta, Part
A, 32A. 851 (1976).
108. A. A. Zinov'ev and A. B. Tsentsiper, Zhur. Neorg. Khim., 4.
724 (1959).
109. A. A. Zinov'ev and V. P. Babaeva, Zhur. Neorg. Khim., 6, 271
(1961).
110. J. B. Levy, 1. Phys. Chem., 06. 1092 (1962).
111. V. P. Babaeva and A. A. Zinov'ev, Dokl. Akad. Nauk. SSSR,
149, 592 (1963).
112. V. P. Babaeva and A. A. Zinov'ev, Zhur. Neorg. Khim., 8, 567
(1963).
113. H. F. Cordes and S. R. Smith, 1. Chem. Eng. Data, 15,156
(1970).
114. R. Gilbert and P. W.-M. Jacobs, Combust. Flame, 17,343
(1971).
115. F. Solymosi, L. Gera, and S. Borcsok, Magy. Kem. Foly., 78,
66 (1972).
116. 0. P. Korobeinichev, G. 1. Anisiforov, A. V. Shkarin, and M.
M. Polyakov, Fiz. Goreniya Vzrva, 9, 199 (1973).
117. M. Kinugasa, K. Kishi, and S. Ikeda, 1. Phys. Chem., 77,
1914 (1973).
118. H. Burton and P. F. G. Praill, Analyst, 80, 4 (1955).
119. H. Fuzellier and A. Herold, C. R. Acad. Sci., Ser. C, 276,
i287 (1973).
120. P. W. M. Jacobs and J. Stevenson, Combust. Flame, 19, 343
(1972).
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Izv. Akad. Nauk. SSSR, Ser. Khim (3), 499 (1973).
122. P. W. M. Jacobs and 1. Stevenson, Combust. Flame, 20,51
(1973).
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Vissh. Khimikotekhnol. inst., Sofia, 19, 245 (1974).
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126. P. Walden, Z. anorg. Chem., 68,307 (1910).
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[*] posted on 29-5-2011 at 13:28
From the shadow's — Perchloric acid hazards


K. Everett and F.A. Graf Jr.
Handling Perchloric Acid and Perchlorates.
In: N.V. Steere, ed. Handbook of Laboratory Safety. Second Edition - 1971.

A violent explosion took place in an exhaust duct from a laboratory hood in which
perchloric acid solution was being fumed over a gas plate. It blew out windows,
bulged the exterior walls, lifted the roof, and extensively damaged equipment and
supplies. Some time prior to the explosion, the hood had been used for the
analysis of miscellaneous materials. The explosion apparently originated in
deposits of perchloric acid and organic material in the hood and duct.

An employee dropped a 7-lb bottle of perchloric acid solution on a concrete floor.
The liquid was taken up with sawdust and placed in a covered, metal waste can.
Four hours later, a light explosion blew open the hinged cover of the can.

A stone table of a fume hood was patched with a glycerin cement and several
years latter, when the hood was being removed, the table exploded when a
workman struck the stone with a chisel.

During routine maintenance involving partial dismantling of the exhaust blower on
a perchloric acid ventilating system, a detonation followed a light blow with a
hammer on a chisel held against the fan at or near the seal between the rear
cover plate and the fan casing. The intensity of the explosion was such that is
was heard four miles away and of the three employees in the vicinity, one
sustained face laceration and slight eye injury; the second suffered loss of four
fingers on one hand and possible loss of sight in one eye; the third was fatally
injured with the 6 in. chisel entering below his left nostril and embedded in the
brain.


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[*] posted on 29-5-2011 at 13:29
Things your mother never told you about the H2SO4 - KClO3 reaction


Action of potassium chlorate on concentrated sulphuric acid. (Preliminary note.)
S. Smith. Chem. Soc. Proc., 1910, 26, 124-125.
In: — The Journal of the Society of Chemical Industry. 29 [12] 754.

The author has observed that at 338o C. the action of potassium chlorate on
concentrated sulphuric acid is entirely unattended by explosive violence, the
addition of the powered salt to the boiling acid merely resulting in a brisk
effervescence, with the production of chlorine , oxygen, and perchloric acid. The
volume of oxygen evolved corresponds with about 90 per cent. of the total
oxygen contained in the potassium chlorate, whilst the amount of perchloric acid
formed appears to be very small. This reaction was studied at various
temperatures, and it was found that from 338o to 200o C. no crackling or
detonation is produced. At 170o C., however, the addition potassium chlorate to
sulphuric acid results in a number of small detonations, which increase in
violence as the sulphuric acid is cooled and reach a maximum between 130o and
120o C., when a sharp explosion results. Below 120o C., the violence of the
action diminishes, until at 60o C., chlorine peroxide is quietly evolved without
crackling or detonation.
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ItalianChemist
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[*] posted on 30-5-2011 at 07:46


The extraction with DCM sound very interesting...could you please send me the solubility of HClO4 in DCM?
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[*] posted on 30-5-2011 at 21:54


Quote: Originally posted by ItalianChemist  
The extraction with DCM sound very interesting...could you please send me the solubility of HClO4 in DCM?


Anhydrous HClO4 forms solutions with dichloromethane. Since the acid is so hygroscopic, it's noted that the when the DCM solution is exposed to atmospheric air moisture, the solution fumes forming white hydroxonium perchlorate (H3O+ClO4-), which is insoluble in DCM, mentioned in doi: 10.1021/ja00735a047.

But there's no reason to believe dichloromethane will be unreactive to perchloric acid. The mixture is already detonable. And if the DCM is methanol-contaminated, there is a pretty good chance of explosion. The topic of solvent extraction of HClO4 was also brought up in this and this thread.

And actually, an attempt to form anhydrous HClO4 solutions of dichloromethane (which was pure) using oleum and conc. HClO4 has already ended in a disasterous explosion on at least one occasion (see attached article).

Attachment: DCMandHClO4.pdf (119kB)
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Quote: Originally posted by The WiZard is In  
Action of potassium chlorate on concentrated sulphuric acid. (Preliminary note.)
S. Smith. Chem. Soc. Proc., 1910, 26, 124-125.
In: — The Journal of the Society of Chemical Industry. 29 [12] 754.

...
action diminishes, until at 60o C., chlorine peroxide is quietly evolved without
crackling or detonation.


Serullas has described explosions just by mixing KClO3 and H2SO4. In the small milligram scale all I've seen was just the gas evolution.

[Edited on 31-5-2011 by Formatik]
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[*] posted on 1-6-2011 at 05:11


Thank you! :D
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[*] posted on 6-6-2011 at 04:10


Red P and H2O2 50% burst into flame after a few seconds.

Glycerol and KMnO4 induction period dependant of the external heat, heat of the reactants and of the KMnO4 granulometry...
So much slower:
-in winter at 0°C than in summer at 30°C.
-in coarse cristals than with fine powderous.
-with frozen glycerol than with ambiant temp glycerol.

Terpentine oil and concentrated HNO3 should burst into flame on contact of each other.




PH Z (PHILOU Zrealone)

"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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