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Watching some movie/TV this question came to mind, purely theoretical of course, if one wanted to dissolve a human corpse, like getting rid of a body after killing someone, is it better to use an acid or a base? In the movies (as well the popular perception for some reason) they always use acid. The movie I was watching they had a bathtub full of acid in which they throw in the body. But I also remember my chem teacher telling me (a long long time ago) that if she had a choice of an acid or a base in her eye, she would take acid any day because a base will dissolve organic tissue faster. So assuming that the acid and base have the same level of strength (say a pH of 1 and 13 respectively) which is better for getting rid of a corpse?

Thanks!

orthocresol
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Fixed Point
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    A note: The people who watch movies may not know what a "base" is, which is why they always use acids (a term known to everyone). – ManishEarth Jan 18 '13 at 11:14
  • The movie was The American version of La femme Nikita, Point of no return, correct? Harvey Keitel, the "cleaner" comes in to get rid of the bodies. he uses acid. – Richardbernstein Mar 14 '13 at 02:52
  • @Tyberius , since this question was asked before the one in your link, shouldn't the linked question be considered the possible duplicate? – airhuff Apr 09 '17 at 03:10
  • @airhuff I did not look at the dates carefully enough so that's my bad. But both of the questions came up as recently active and I think one of these should become the primary question and the other a duplicate to avoid multiple questions on the same topic. – Tyberius Apr 09 '17 at 03:19
  • @Tyberius , I completely agree. – airhuff Apr 09 '17 at 03:22
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    @airhuff regarding closing an older question as a dupe of the newer question, you may be interested in https://meta.stackexchange.com/q/147643/312770 – orthocresol Apr 09 '17 at 14:07
  • @Tyberius see above comment ^ – orthocresol Apr 09 '17 at 14:07

4 Answers4

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I would say that acids are better.

Why? Bases and acids dissolve flesh pretty easily (I'm thinking of $\ce{NaOH}$ and $\ce{HCl}$ here, weaker acids/bases -- not so much). Most of our body is made up of proteins, which are overall pretty much neutral (generally). Both acids and bases can dissolve protein.

On the other hand, there is one major component of our body which is easier to dissolve with acid. Bones. The major component of bone is $\ce{CaCO3}$. The reaction $\ce{2HCl +CaCO3 -> H2O + CO2 ^ + CaCl2}$ is much more efficient/faster than $\ce{2NaOH + CaCO3 -> Na2CO3 + Ca(OH)2}$. Why is this? Well, for one, in the acid reaction, a gas is being released. This speeds up the reaction, by Le Châtelier's principle.

Apparently, NaOH is not able to dissolve bone completely, you are left with a fragile shell. Either way, it will be much slower than $\ce{HCl}$ while dissolving bone.

Here's an interesting article (no claims on validity) of why lime shouldn't be used to dissolve a corpse.

While (as far as I can tell) acids may be the better way to dissolve a body, I feel that filmmakers use acids because the term is known to most of the general public (unlike "bases", which isn't)

ManishEarth
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  • And if you pick nitric or sulfuric acid to dissolve bone, then you get $\ce{Ca(NO3)2}$ or $\ce{CaSO4}$, both of which are even more soluble than $\ce{CaCl2}$. – Ben Norris Mar 14 '13 at 10:30
  • ... Except those acids are harder for the average cleaner to get their hands on. Muriatic acid is available at any home improvement store, for a variety of uses, primarily pool chemistry. – KeithS Mar 15 '13 at 01:00
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  1. Chop the body into smaller pieces, using a sturdy butcher axe.
  2. Use a pressurized stainless steel autoclave (preferable with stirrer) or comparable professional kitchen equipment, suspend the pieces in concentrated $\ce{NaOH}$ and apply heat!
  3. Cool down, release pressure and check. Saponification of body fats releases fatty acids that might form protective films and thus prevent further rapid decomposition of the "biological material". If necessary, stir and repeat until the meat is converted to a sludge.
  4. Dispose the sludge, wash the bones, crush them to smaller pieces (= larger surface) and dissolve them in conc. $\ce{H2SO4}$.
  5. Bring something to read - just in case you have to spend some 30+ years in a locked room - a book on Adolph Luetgert would be an obvious choice :D
Klaus-Dieter Warzecha
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Hot concentrated aqueous lye will dissolve tissue, aided by the process making soap. Bone is about 50 wt-% hydroxylapatite, calcium phosphate, $\ce{Ca10(PO4)6(OH)2}$. That is a problem. Calcine, then make

http://en.wikipedia.org/wiki/Bone_china

http://en.wikipedia.org/wiki/MythBusters_(2013_season)
Mythbusters (Episode 208) demonstrated that acid as such is not effective for dissolving bulk flesh. "Piranha solution" (concentrated hydrogen peroxide in concentrated sulfuric acid) eats organics, oh yes indeed, and can explode while doing it; while making it, too.

Uncle Al
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There's an interesting documentary on how to dissolve organic tissue on YouTube: How to Commit the Perfect Murder, a BBC Horizon Documentary

They demonstrate that a washing powder is the best for dissolving organic tissue provided you can heat it up a bit.

jonsca
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Peter
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