Whats the most dangerous chemical you have used / seen?

[Arthur Dent]

The scariest mofo is indeed ClF3... out of control reactive with almost everything! Even the most basic handling of this stuff requires dramatic precautions and if there's a leak of this stuff in a lab... kiss the lab goodbye and run away like you're doing the 100 meter sprint!

 

The scariest stuff I own is HNO3. I greatly respect the 2.5 L glass bottle I have.

 

Robert

[hypervalent_iodine]

alpha-d-glucopyranosyl-(1->2)-beta-d-fructofuranoside

Also known as sucrose.

[kristina221]

Picric acid, aresenic and cromyl chloride(CrO2Cl2). The last one gave me a headache that lasted for 2 days...

[Horza2002]

Osmium tetroxide (highly posionous in contact with skin), phosphorous tribromide (generally very nasty and brominates just about anything it touches), t-BuLi (nasty but gives a pretty red flame if your let it touch air), selenium dioxide, sodium cyanide (no explanation needed) and hydrofluroic acid...think thats it for the last year.

[DrRocket]

Mods: Is this acceptable, I am not asking people how they made the stuff, where they got it etc. I'm just wondering what the most dangerous thing you think you've seen / used

 

I saw these when we were clearing out an old cupboard in the chemistry lad last week:

 

I think the most dangerous chemical I have ever seen was something labelled [ce]Hg(ONC)_2[/ce] and it was in the back of one of the school chemistry cupboards... I did some reasearch and this stuff is explosive. My chemistry teacher said he never knew it was there - he said it has probably been there for years, the next day the bomb squad were called up to remove the stuff... I just wish I could have seen it explode!

 

Or... it may have been the really concentrated solution of Hydrogen Peroxide, I've heard that stuff is pretty powerful. My teacher managed to dispose of that one - I'm not shure how he made us leave the room incase of any problems. Apparently it was about 83% concentrated but I'm not shure about that.

 

Edit: then again, the Nitrogen Triiodide reaction was pretty powerful - I'm staying clear of that one too!

 

Anyone else have anything interesting to share? Please do not post how to make the stuff - danger is bad!

 

Cheers,

 

Ryan Jones

 

A nitroglycerine storeage tank .

[hypervalent_iodine]

Picric acid, aresenic and cromyl chloride(CrO2Cl2). The last one gave me a headache that lasted for 2 days...

 

On the topic of picric acid, a few years ago there was a couple of barrels of it found on the top level of the math/astrophysics building at uni. Been there for years. I like to think it was the doing of a very patient chemist, trying to knock mathematicians off from their position at the top of the heirachy with brute force. This is just in the same that way our chemistry building is specifically designed to explode outwards and take out maths, molecular biosciences and engineering, should it ever be blown up. The latter two are clearly just for fun.

[kristina221]

When we ignated a bit of picric acid(about 1 g) it burned through the asbestos heating net...

[skwiff]

When we ignated a bit of picric acid(about 1 g) it burned through the asbestos heating net...

 

 

AWESOME!!!!

 

any way, the most dangerous chemicals ive used to date, is (please bare in mind im on a A-level standard course) 5mol aprox HCl, a solution of KCr2O7 the HCl stang like hell when i accidently inhaled it i was only using 5ml but this was enough to trigger a coughting fit that came on and off the remainer of the day! not pleasent

[Dan_Ny]

I remeber being an undergrad and having to use half a gram potassium cyanide for a benzoin condensation.

 

On the topic of picric acid, a few years ago there was a couple of barrels of it found on the top level of the math/astrophysics building at uni. Been there for years. I like to think it was the doing of a very patient chemist, trying to knock mathematicians off from their position at the top of the heirachy with brute force. This is just in the same that way our chemistry building is specifically designed to explode outwards and take out maths, molecular biosciences and engineering, should it ever be blown up. The latter two are clearly just for fun.

 

:D Awesome...

Edited March 12, 2011 by Dan_Ny

[skwiff]

Who does that to undergraduates?

 

 

horrible tutors?

[Dan_Ny]

horrible tutors, yes. i remember my OC tutor from my third semester as an undergraduate. horrible is a friendly word for what he was. or is?

Edited March 14, 2011 by Dan_Ny

[ajb]

What about alcohol? It has destroyed many lives and split up many families. Is this the most dangerous chemical we know?

[skwiff]

What about alcohol? It has destroyed many lives and split up many families. Is this the most dangerous chemical we know?

 

 

errr thats more cronic use... not so much "woot i've found the bottle in the cupboard" *shakes the powder inside, not relising its picric acid* BOOM! no more science fool...

[ajb]

errr thats more cronic use... not so much "woot i've found the bottle in the cupboard" *shakes the powder inside, not relising its picric acid* BOOM! no more science fool...

 

Still, one can make a good case for the danger of alcohol. It depends on how you want to measure or define dangerous.

[John Cuthber]

Still, one can make a good case for the danger of alcohol. It depends on how you want to measure or define dangerous.

You can, and I did. About a year ago in this very thread..

[skwiff]

dichlorine methane on plastic... it melted a hole in my fridge

[hypervalent_iodine]

dichlorine methane on plastic... it melted a hole in my fridge

 

It will do that.

 

Even more horrible is DCM and contact lenses. The vapours will react with the polymers in the lenses and cause them to adhere to your eyes.

[Dan_Ny]

It will do that.

 

Even more horrible is DCM and contact lenses. The vapours will react with the polymers in the lenses and cause them to adhere to your eyes.

 

Cruel. I know why I wear my lab glasses.

[Horza2002]

Yep...if you ever needed a reason not to wear contacts in the lab thats it....just get percription safety specs like mine...not only are they safe, they damn sexy too!

[skwiff]

It will do that.

 

Even more horrible is DCM and contact lenses. The vapours will react with the polymers in the lenses and cause them to adhere to your eyes.

 

 

i know some one who was studying for her masters and another student done up the bottle of DCM too tight and it broke! she said the lab had to be evacuated and the students took it in turns to mop up the spillage until they 'felt dizzy'!

[Djordje]

Acetone Peroxide - easy to make, did it once, unstable - 2 grams ignited by friction of paper bag it was in - friend got little burned

Aqua regia - solution of HNO₃ and HCl in proportion 1:3 - extremely corrosive (gold dissolves in it).

[Periodic Acid]

dihydrogen monoxide

[Ziconotide]

Cyanides are not dangerous...same thing for common reagents in the lab. Do you really want 2 know REALLY dangerous materials? So toxic, that one exposure 2 them can be deadly? I will give some examples of EXTRAORDINARY toxic materials:

 

Botulinum toxin

 

Ricin

 

Abrin

 

Diphteria toxin

 

Dimethyl mercury

 

Methyl isocyanate

 

Batrachotoxin

 

Aflatoxins

 

Taipoxin

 

GF nerve agent (cyclosarin)

 

GD nerve agent (soman)

 

Dimethyl sulfate

 

Saxitoxin

 

Aconitine

 

Palytoxin

 

Maitotoxin (extremely nasty)

 

These are the chemicals of Hell, deadly as Grim Reaper's scythe

 

 

[skwiff]

Cyanides are not dangerous...same thing for common reagents in the lab. Do you really want 2 know REALLY dangerous materials? So toxic, that one exposure 2 them can be deadly? I will give some examples of EXTRAORDINARY toxic materials:

 

Botulinum toxin

 

Ricin

 

Abrin

 

Diphteria toxin

 

Dimethyl mercury

 

Methyl isocyanate

 

Batrachotoxin

 

Aflatoxins

 

Taipoxin

 

GF nerve agent (cyclosarin)

 

GD nerve agent (soman)

 

Dimethyl sulfate

 

Saxitoxin

 

Aconitine

 

Palytoxin

 

Maitotoxin (extremely nasty)

 

These are the chemicals of Hell, deadly as Grim Reaper's scythe

 

 

 

palytoxin and maitotoxin are the most toxic non-peptide based toxins in existance... but the are spat on by botutoxin

[Anders Hoveland]

Dichlorine heptoxide, Cl2O7, is dangerous is several unusual ways.

 

95-100% Concentrated Perchloric Acid

 

Physical Properties

 

Pure perchloric acid is unstable. If left standing at room temperature for between 10 and 30 days, at some point the temperature of the acid will spontaneously rise to 90 degC, at which point there will be an explosion. Pure perchloric acid cannot be distilled at ordinary pressures. To avoid partial decomposition (into Cl2, O2, and various chlorine oxides), distillation must be done below 200 mmHg.

 

Reactivity

 

"I would expect CH2Cl2 to react with HClO4 (if not sooner, then later), since HClO4 seems to react with both CHCl3 and CCl4, and CH2Cl2 is less oxidized. I would be especially careful with CH2Cl2, it should easily be at least a detonable mixture.

 

Namely, HClO4 is entierly miscible with CHCl3, the solution discolors after a few days to yellow, and in air sheds crystals of HClO4.H2O. Commercial chloroform contains alcohol, which sheds a heavy, with CHCl3-insoluble extraordinarily explosive oil (Vorländer, v. Schilling, Lieb. Ann. 310 [1900] 374; Vorländer, Kaascht (Ber. 56 [1923] 1162).

 

For CCl4, HClO4 is insoluble in CCl4, and gives upon shaking, a green emulsion, which discolors brown after several minutes welling up under formation of HCl and COCl2 (Vorländer, v. Schilling, Lieb. Ann. 310 [1900] 374). Preparation of solutions of Cl2O7 in CCl4 described in: F. Meyer, Keszler (Ber. 54, [1921] 569).

 

the interaction of HClO4 with benzene has been described as follows:

If one to two drops of HClO4 has 2 to 3 cm3 benzene poured over it, under heat evolution brown flakes precipitate. Mixing of equal volumes at first forms a green emulsion, which then explodes (Vorländer, v. Schilling, Lieb. Ann. 310 [1900] 374). 1 g of HClO4 solubilizes in 5g of well-cooled benzene under formation of a green solution, which when stored in a sealed tube, discolors increasingly shedding a carbon-containing material; after completion of the reaction, no free acid is found anymore (Michael, Conn, Am. chem. J. 23 [1900] 444).

 

So mixing something like CCl4 and HClO4 can cost one their lives if not wearing protective gear, doing under fume hood,etc. It is dangerous to extrapolate so assuredly."

 

 

Dichlorine Heptaoxide (perchloric anhydride) Cl2O7

 

Physical Properties

Cl2O7 melts at (minus) -91.5 degC and boils at 80 degC. At 0 degC, it has a vapor pressure of 23.7 degC. Cl2O7 has a density of 1.86 g/mL. Cl2O7 decomposes spontaneously on standing for a few days. Cl2O7 decomposes into chlorine and oxygen under very low pressures (below 80mm Hg) or in the temperature range of 100-120 degC. Cl2O7 is soluble in benzene, slowly attacking the solvent with water to form perchloric acid. Cl2O7 detonates when heated or when subject to mechanical shock. It explodes on contact with flame or by percussion.

 

Chlorine heptoxide is more stable than either chlorine monoxide or chlorine dioxide; however, the anhydride detonates when heated or subjected to shock.

 

Reactivity

Cl2O7 is soluble in benzene, slowly attacking the solvent with water to form perchloric acid; it also reacts with iodine to form iodine pentoxide.”

 

Benzene reacts with Cl2O7 However this seems to contradict something else I read. "Cl2O7 is a strong oxidizer as well as an explosive that can be set off with flame or mechanical shock, or by contact with iodine. Nevertheless, it is less strongly oxidising than the other chlorine oxides, and does not attack sulfur, phosphorus, or paper when cold."

Holleman, Arnold F.; Wiberg, Egon (2001). Inorganic chemistry. Translated by Mary Eagleson, William Brewer. San Diego: Academic Press. p. 464. ISBN 0123526515.

^ Byrns, A. C.; Rollefson, G. K. (1934). Journal of the American Chemical Society 56: 1250–1251.

 

So Cl2O7 reacts with benzene, but not paper or phosphorous when cold? One explanation might be that a protective layer is formed that prevents further oxidation. P2O5 is known to form an adhesive layer on reaction with water that limits further hydration, for instance. However, failure of Cl2O7 to react with sulfur cannot be explained by a protecting layer, since nothing could form that would not be soluble or a gas. HNO3 attacks sulfur, but not benzene, so I have difficulty believing that Cl2O7 would react in an opposite way. Thus this is all quite confusing, and to make any sense of the conflicting references is a logic puzzle.

 

Cl2O7 does not explode on contact with wood, paper or similar materials but just evaporates (Michael, Conn, ibid). They also note unreaction towards sulfur and phosphorus pieces. HClO4 on the other hand does explode violently on contact with wood and paper, and especially charcoal (Roscoe, Lieb. Ann. 121 [1862] 353).

 

Cold, dry C6H6 solubilizes Cl2O7, then soon afterwards a reaction occurs (A. Michael, Conn, Am. chem. J. 23 [1900] 446).

 

Cl2O7 reacts with iodine to form iodine pentoxide (I2O5). Addition of iodine to Cl2O7 can result in explosion, however, so the reaction is probably best done diluted in an appropriate solvent.

 

 

Other compounds related to Cl2O7

 

Perchloryl fluoride (FClO3) is very stable, poisonous and reactive (Bp. -46.7C, Mp. -147.7C). Electrolysis of satd. NaClO4 in anhydrous HF yields the compound. Another way in 85-90% yield, is to warm a mixture of KClO4, HF and SbF5 at 40-50 C (Kirk Othmer). FClO3 is also stable up to 400 C, and hydrolyzes slowly. Grease and rubber tubing has caused explosions, for more reactivity see Brethericks.

 

The German wikipedia claims alkali fluorides reacting with Cl2O7 does yield FClO3, though no exact reference is given for this.

 

Hantzsch claimed to have made fluoronium perchlorate [FH2]ClO4 by reacting anhydrous HClO4 with anhydrous liquid HF, which under strong heat evolution was said to yield solid [FH2]ClO4 (Ber. 60 [1927] 1946), and which compound he said reacts explosively with H2O (Ber. 63 [1930] 97). Brauer and Distler (Z. anorg. u. allgem. Chem. 275 [1954], 157) tried to make this compound, but could not repeat preparation despite mixing in various ratios and temperatures.

 

FClO3 is also made by reacting fluorine with KClO3 at -20 C in SbF5: KClO3 + F2 = KF + FClO3 Or by reacting KClO4 with HSO3F: KClO4 + HSO3F = FClO3 + KHSO4 (From: Lehrbuch der anorganischen Chemie by A.F. Holleman, E.Wiberg, N.Wiberg). On the last one, no more decent details given by Holleman et al., it could react right away or may need some warming, time to hit the more serious lit.

 

With ammonia, FClO3 forms a perchlorylamide: FClO3 + NH3 = ClO3(NH2) + HF. This has acidic protons and they are replaceable by metal ions: K[ClO3(NH)] and K2[ClO3N] these are colorless, up to 300 C stable compounds, which explode by impact.

 

"Dichlorine hexoxide is a dark red fuming liquid at room temperature that crystallizes as an ionic compound, chloryl perchlorate, [ClO2]+[ClO4]−. Many other reactions involving Cl2O6 reflect its ionic structure, [ClO2]+[ClO4]−, including the following:

NO2F + Cl2O6 → NO2ClO4 + ClO2F "