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In the TV show "Breaking Bad", Walter White frequently gets rid of people who get in his way by submerging them in a plastic container full of hydrofluoric acid. This, at least in the TV show, completely dissolves the body leaving nothing but a red sludge behind at the end.

Is it actually possible to dispose of a body with hydrofluoric acid?

If hydrofluoric acid wouldn't work, are there any acids corrosive enough to achieve the stated effect from the show?

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    $\begingroup$ I can't say if this is possible, but concentrated HF poses a very real threat of delayed, life threatening damage by scavenging calcium from the body, either by splash or inhalation. HF is not a strong acid, but its toxicity makes it substantially more dangerous to work with than many strong acids. I tend to think that dissolving a body would be quite difficult, and then you'd have the scrub the bathtub ring... $\endgroup$ – Richard Terrett May 3 '13 at 12:29
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    $\begingroup$ Related: chemistry.stackexchange.com/questions/3949/…. I wonder when the FBI will come and shut this site down for answering questions about disposing bodies and FOOF ;-) $\endgroup$ – ManishEarth May 3 '13 at 15:33
  • $\begingroup$ I guess he used fluoroantimonic acid. :) $\endgroup$ – user11343 Dec 17 '14 at 3:50
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    $\begingroup$ or hydrogen peroxide and conc sulphuric acid .. oops there's another finger gone! $\endgroup$ – porphyrin Aug 16 '16 at 22:25
  • $\begingroup$ I like people who makes experiments Periodic Video I was not a lot of surprised by the experiment, but it is always good to see what happend in an other place than a movies beacause it may sometimes be false. Now I can come back dissolving my stepmother... :) $\endgroup$ – Hexacoordinate-C Oct 13 '16 at 14:43
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Hydrofluoric acid is toxic and corrosive, but actually isn't that strong of an acid compared to other hydrohalic acids; the fluorine has a very good orbital overlap with hydrogen and is also not very polarizable, therefore it resists donating its proton, unlike other hydrohalic acids which are good proton donators. It will break down some tissues, but it will take a relatively long time and won't turn the entire body into stuff that can be rinsed down the drain. Hydrochloric acid is a much stronger acid, and as it has several uses from pH-balancing pool water to preparing concrete surfaces, it's available by the gallon from any hardware store. However, it isn't very good at dissolving bodies either; while it will eventually work by breaking down the connective tissues, it will make a huge stink and take several days to dissolve certain types of tissues and bones.

The standard body-dissolving chemical is lye aka sodium hydroxide. The main source is drain clog remover because most drain clogs are formed by hair and other bio-gunk that accumulates naturally when humans shower, exfoliate etc. It works, even though the body's overall chemistry is slightly to the basic side of neutral (about 7.35-7.4) because the hydroxide anion is a strong proton acceptor. That means that it strips hydrogen atoms off of organic molecules to form water (alkaline hydrolysis, aka saponification), and as a result, those organic molecules are turned into simpler molecules with lower melting points (triglycerides are turned into fatty acids, saturated fats are dehydrogenated to form unsaturated fats, alkanes become alcohols, etc). Sodium hydroxide is also a ready source of the sodium ion; sodium salts are always water-soluble (at least I can't think of a single one that isn't). The resulting compounds are thus either liquids or water-soluble alcohols and salts, which flush down the drain. What's left is the brittle, insoluble calcium "shell" of the skeleton; if hydrolyzed by sodium hydroxide, the resulting calcium hydroxide ("slaked lime") won't dissolve completely but is relatively easy to clean up.

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    $\begingroup$ I like the wording here: "standard body-dissolving chemical" $\endgroup$ – DarkLightA May 13 '13 at 21:20
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    $\begingroup$ I like how you answered the question in the first 6 lines of your response, then graced us with another 12 lines of 'how you should do it' information. $\endgroup$ – LordStryker Dec 18 '13 at 14:33
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    $\begingroup$ "the fluorine is too electronegative to readily donate its proton." What does that mean? If anything, from EN trends alone, we should expect HF to be a strong acid, since the F, as you said, is very EN and is therefore isolating electron density away from the H and thereby making the H more partially positive and more reactive. That's not the case, as there are other, greater factors in play here, such as conjugate stability. The F- anion simply isn't as stable as the Cl- anion, for example. $\endgroup$ – Dissenter Jul 13 '14 at 17:03
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    $\begingroup$ What I mean is exactly what I said. Larger anions have higher-energy orbital shells which spread the negative charge of the electrons over a greater space, meaning that the proton is similarly held at greater distance and with reduced attraction to the anion, so the compound more readily dissociates and donates protons. Fluorine is small, and its electron configuration is the densest available of the halogens. So, the attraction to the proton is increased due to the more concentrated charge, thus requiring more energy to break this ionic bond and form another. $\endgroup$ – KeithS Jul 14 '14 at 15:40
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    $\begingroup$ $\ce{NaBiO3}$ is insoluble in cold water $\endgroup$ – Jan Aug 16 '16 at 23:31
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I think the use of Hydrofluoric Acid was script-driven rather than fact driven: it sounds scary rather than being a good choice. Also, it allows for the possibility of the darkly comic bathtub scene where the acid dissolves a ceramic bath because Jessie ignores Walter's instructions (which establishes Walter's expertise and Jessie's lack of it).

There is no good reason why Pinkman and White pharmaceuticals needed to have hydrofluoric acid, therefore using large quantities of it is somewhat implausible.

Moreover, it probably wouldn't work as well as several alternatives. Hydrofluoric acid is very nasty stuff, but it isn't a strong acid. Even when dilute it will etch glass and ceramics, but it won't dissolve or burn flesh. I once saw a demonstration where a lecturer showed this by spilling some dilute hydrofluoric acid on his hand and then onto a glass surface. The surface was frosted, his hand unharmed (he was very careful to wash the acid off quickly and take appropriate precautions and I don't recommend trying this at home!)

Its danger to people is its toxicity, not its ability to burn: it insinuates itself into the body and destroys connective tissue and bone slowly by interfering with anything containing calcium. Its danger is worse because it doesn't cause immediate damage and you may receive a dangerous dose without noticing. So it is scary but not corrosive.

Other alternatives are better. Concentrated alkalis such as Sodium Hydroxide are readily available and are very good at dissolving flesh (which is why they are commonly used as drain cleaners). But alkalis don't do a good job on bone. Concentrated sulfuric acid is even better as it does a good job on flesh and will, eventually, dissolve the bone as well. Murderers have used both methods to try to dispose of evidence. For example, John George Haigh who used sulfuric acid and left little other than gallstones (http://en.wikipedia.org/wiki/John_George_Haigh). Using alkali is often done but tends to leave bone fragments even with sophisticated processes that pressure cook the solution (see http://www.slate.com/articles/news_and_politics/explainer/2009/12/soluble_dilemma.html).

So I think the answer is that HF solutions are not a good choice for body disposal as it probably doesn't work well compared to known alternatives.

Update

A lot of the above is theory but good scientists do experiments. So Periodic Videos decided to test this very idea using chicken legs as a model. They compared what happens when raw chicken legs are suspended in strong solutions of HCl, H2SO4 and HF. The HF was the least impressive for flesh-dissolving characteristics, though it did seem to cause other, more subtle damage, to the components of the flesh.

See the actual results here.

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Here in Mexico, a guy was arrested a couple years ago for "dissolving" more than 300 bodies killed by the cartels. They found 55-gallon drums around town with a sludge in it, usually with a note to warn other. His recipe? A 55-gallon drum, several bags of lye, add body, fill with h20, and build fire beneath drum.

It took about 24hrs I believe.

Sorry, I got caught up In the comments. And I'm New to this and all (bulletin boards?) Like the case in Australia with sealed drums w/ HCL, in a bank vault, it Actually did more to preserve the bodies. I am no chemist, but it is my understanding, that when acids burn the skin the results are the same for both Fire and chemicals burns both rapidly dehydrate the body, destroying it. But is in a sealed container, that water can only go to the lid. Stopping the process. I bet any acid will destroy a body. When you're in the bath or pool too long you get those wrinkles, I've heard of people with wet feet in boots for weeks, remove their boots, and literally stripping the flesh off their feet to the bone.

The issue is how long will it take like the method used in here in Mexico and another post, boiling seems to be an important component. And again I'm guessing (and vegetarian), the heat tenderizes the meat, helping the acid along, but also the rolling of the water stirs it. If you were to put a piece of meat in acid that was stagnant, the acid might react, dissolve some meat, as the dissolved meat dilutes the acid depending on the makeup. It could settle or form a layer of meat/acid that sits on top of the meat, protecting it. Think layered shots. Or a unflushed end toilet that has had time to settle. Hydrofluoric acid will eat thru skin, google it. One of the reasons the burns are so bad is @ 50%, it can take 8 hours to realize you were burned. So that would be a slow process, and fluoride, as we know, preserves teeth, by extension bones. And for hydrofluoric acid burns, the standard treatment is calcium. So it would be very slow, very likely stop, possible preserve the bones, making the resistant to rotting and harden them, but as your, we'll my fingers have less meat than most parts of my body, it would get to bone faster, ossicle dissolving some calcium, then render all the acid useless. Again I am not a chemist but have self-studied chemistry for years, I would be very interested to hear anyone else's opinions on my determinations!

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  • $\begingroup$ Interesting answer! But the question is related to hydrofluoric acid can you be more precise? Thank you! $\endgroup$ – G M Jul 13 '14 at 16:50
  • $\begingroup$ I removed the portions not related to the science. $\endgroup$ – jonsca Jul 13 '14 at 18:55
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I believe dilute boiling hydrochloric acid is quite destructive to all flesh and bones. You don't want a concentrated acid as it has annoying oxidation effects which slow the reaction. You don't want hydrofluoric as its hideous dangerous to handle at all temperature (a small amount on your skin will be absorbed and lead to inevitable death if you don't inject calcium glutamate into you) and the formation of insoluble calcium fluoride (and others) slows everything down.

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This subject is touched upon here and explained in detail on this Wikipedia page.

Essentially, it is impractical to dispose of a body using an acid, though there exists a process called alkaline hydrolysis, which, as its name implies, makes use of a base to degrade the materials comprising the human body to a liquid state within a matter of hours.

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A man here in Australia dissolved his wife's body in Hydrochloric acid in a wheelie bin. He put her body in the bin and poured 20 liters of Hydrochloric Acid in it. Then 2 days later went and bought another 40 liters and topped it up until everything was liquid. He then poured it down a storm drain and rinsed it all out with water. The only thing they found was her prosthetic teeth. Basically, once the Acid stops dissolving and becomes weak, you have to keep adding more. But it will eventually dissolve a whole human body.

Cairns man Klaus Andres, who admitted to dissolving wife's body in acid, guilty of murder, jailed for life http://www.abc.net.au/news/2013-12-12/cairns-man-guilty-of-murdering-wife/5152488

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I know this is an old question, but it gets viewed a lot so I thought I would update with the fact that this experiment was actually done on the first Mythbusters Breaking Bad special, episode 206. There is a description of the results of the episode inside that link.

Is it actually possible to dispose of a body with hydrofluoric acid?

To summarize from the Mythbusters episode, they tested out hydrofluoric acid on various small scale materials (to simulate the bathtub) as well as pig parts (the body) and found that $\ce{HF}$ certainly deteriorates some of the materials, but not at anything close to the same speed as in the show. It is even less successful at decomposing the actual flesh than the materials. One way of viewing this is to remind yourself that the ability of $\ce{HF}$ to eat through materials actually has more to do with fluorine's reactivity than with the ability to give a hydrogen atom (it is classified as a weak acid), thus it's reasonable that $\ce{HF}$ might be better at disrupting the structural integrity of metals/polymers than acidically eating through flesh.

See this question for details about its reactivity with glass. Mythbusters notes that a fiberglass bathtub actually would've behaved similarly to what we see in Breaking Bad, but over a much longer timescale.

So it's perhaps feasible to dispose of a body with $\ce{HF}$ given a very large amount of time, but it's not possible in the timescale presented in the show.

If hydrofluoric acid wouldn't work, are there any acids corrosive enough to achieve the stated effect from the show?

The real reason I brought up this episode of Mythbusters is that they have a storied tradition of reproducing the results at all costs. In this episode, at the end, they fill up a bathtub with 140 L of concentrated sulfuric acid, a "secret sauce", and a whole pig just to see what happens...

To borrow the words of the episode description from the link above,

After 5 minutes, Adam and Jamie found only black organic sludge where the pig used to be.

And, a word on the secret sauce. Intuition says that this is something which is going to be good at breaking down organic matter. I looked around and found some people speculating on this reddit post, and they come up with pretty convincing evidence that the "secret sauce" is just hydrogen peroxide.

Hydrogen peroxide is a good radical initiator, and thus should be quite effective at assisting in the decomposition of this pig/person. This mixture actually has a name: piranha solution.

So, to answer, yes, a mixture of $\ce{H2SO4}$ and $\ce{H2O2}$ should do the job.


I know Mythbusters and Reddit aren't exactly the standards of scientific authority, but in this case, I think they're doing pretty well.

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protected by Martin - マーチン Dec 17 '14 at 4:05

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