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In the "Cat's in the Bag..." episode of Season 1 of "Breaking Bad," characters are shown with 4 gallon-jugs of Hydrofluoric Acid that they use to dissolve 2 adult corpses. Chemistry is a major plot device in the show and it seems like they go to some effort to keep those elements based in reality.

According to this article, hydrofluoric acid is a good choice for your body-melting needs. But if a bath is usually around 200 liters (50 gallons), could you really do it with just a few (5-10 liters, 2-4 gallons) of acid?

It's worth pointing out that for the purposes of this question, "dissolve" is defined as "creating a toilet-flushable slurry."

Sklivvz
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Larry OBrien
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  • Without doing experiments it is hard to be sure, but I'd say that glacial sulphuric acid would do the job faster (and wouldn't eat through the ceramic bath). Aqueous solutions are actually weak acids (I once had a lecturer demonstrate this by pouring some over his hand into a glass petri dish; his hand was OK but the glass was frosted. NB don't try this at home, it will poison you if you don't wash the acid away quickly). – matt_black Jun 23 '13 at 18:55
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    @matt_black [HF is unique among the acids in its ability to penetrate intact skin. It diffuses through the tissues and disassociates into the hydrogen ion and the fluoride ion.](http://webcache.googleusercontent.com/search?q=cache:MzG7v5gXIMIJ:www.phy.cam.ac.uk/hands/hazards/chemicals/Hydrofluoric%2520acidusers.doc) – ChrisW Jun 23 '13 at 18:58
  • There exists a similar 'claim' in the french film version of _La Femme Nikita_: in which "Victor the cleaner" dissolves bodies in a bathtub using 4 x 500ml bottles from his briefcase, which are labelled (on screen) "acid / skull and crossbones / dangerous" (but not specifying the type of acid). – ChrisW Jun 23 '13 at 19:11
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    I don't think the claim, as questioned, is notable. They actually used enough acid to, along with the body, fill a 55-gallon barrel. That's a LOT MORE than 2-4 gallons. – Flimzy Jun 23 '13 at 19:14
  • @Flimzy I think you're thinking in later seasons, when Walter is in more of an industrial setting. In the first, Walter grabs a handful of jugs from his HS chemistry lab. And they don't use a barrel, but a bathtub (to disastrous effect). – Larry OBrien Jun 23 '13 at 20:04
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    I don't think this question deserves to have a negative score. – Sklivvz Jun 23 '13 at 20:31
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    @LarryOBrien: Remember Walter's instructions to Jesse to buy large plastic tubs? I think it's safe to assume they were planning to use large quantities (> 4 gallons) of acid. I also think the first time a body was dissolved, the quantity of acid used was very ambiguous. I don't think it's possible to conclude they used only 2-4 gallons. – Flimzy Jun 23 '13 at 20:54
  • @ChrisW Yes, but that is as much about poisoning as about dissolution. – matt_black Jun 23 '13 at 22:22
  • They use the same technique in episode 1 of series 4, but this time they put the body in a big plastic tub first. – matt_black Jun 23 '13 at 22:27
  • @Flimzy "I think it's safe to assume they were planning to use large quantities..." Well, within the context of the show we'd expect Walter to use the *necessary* amount and that's my question. They definitely imply an "on hand" amount -- he grabs gallon jugs from shelves on his HS supply closet and they have another scene where 4 jugs are strewn around Jesse's living room. – Larry OBrien Jun 23 '13 at 23:52
  • in my high-school chem class I learned that acid is good to get rid of the bones and alkaline is good to get rid of the soft tissue – ratchet freak Jun 24 '13 at 00:54
  • *Even if* they only used 4 gallons in the show, I don't think that makes the quantity used a notable claim. Especially in light of the many other scientifically-ridiculous things they do in the show (the [electromagnet](http://movies.stackexchange.com/q/11627/22) from S5 comes to mind as a prime example). The show's "science" is based on loosely science (electromagnets do exist), but the details are based on fantasy (EM fields are short). I think the acid "claim" in the show is sufficient for "Can Hydrofluoric acid disolve a body?" I don't think the 4-gallon part makes for a notable claim. – Flimzy Jun 24 '13 at 03:12
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    Not an answer, but please don't play with HF at home or school... HF is unusually dangerous because it soaks through skin, reacts exothermically with bone venting H2, and binds quickly to Ca and Mg in fluids making the body fatally deficient -- research safety policies are an issue at many college campuses. http://web.utk.edu/~ehss/training/has.pdf‎ – Paul Jun 24 '13 at 04:59
  • There's a court case underway now dealing with a murder where the victim was cut in pieces and then stored in barrels of acid in order to destroy the evidence. http://nos.nl/artikel/353222-om-familie-loste-lijken-op-in-zuur.html They used the less potent (but more available) hydrochloric acid. A google search showed a surprising number of similar cases. – jwenting Jun 24 '13 at 05:41
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    They tried it on Mythbusers. – liftarn Mar 17 '15 at 14:26

2 Answers2

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From chemistry.stackexchange.com:

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 to readily donate its proton. Hydrochloric acid is much stronger, 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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George Chalhoub
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It isn't the amount of HF that is notable it is whether HF will work at all in this context. HF sounds like a good way to dissolve bodies as it has a fearsome and dangerous reputation in chemistry. But that reputation is based on the fact that it is a dangerous biological poison not on its ability to "dissolve" flesh. It is, in fact, a weak acid and not that good as a way to turn flesh into a flushable mush.

From my answer on the chemistry.se site (explaining the script choice):

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).

Moreover, we don't have to rely on theory here, the experiment has been done. Periodic Videos tested the idea using raw chicken legs and several flesh-dissolving alternatives. This video shows that, while HF has some remarkable effects on flesh, dissolving it into a mush isn't something it does quickly.

Incidentally, chemistry.se tagged this, amusingly, as everyday-chemistry.

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matt_black
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  • This would fit with the show's habit of changing details of how certain criminal acts are performed (most notably, cooking meth). – KSmarts Mar 24 '15 at 17:04