FAQ
It is currently Sun Oct 22, 2017 4:41 am


Author Message
jimmydasaint
Post  Post subject: What Damage Can a Concentrated Acid Do?  |  Posted: Tue Jun 05, 2012 5:38 pm
User avatar

Joined: Fri Aug 12, 2011 4:53 pm
Posts: 380
Location: Farnham Royal, Bucks

Offline
I have seen the aftermaths of some horrific acid attacks on, mostly women (how mysoginistic is that?) from husbands or boyfriends. However, I wondered what it does to living tissue from a mechanistic point of view. Which molecules are damaged and how? Any ideas?

http://www.dailymail.co.uk/femail/article-1221077/Katie-Piper-Acid-attack-victim-bravely-shows-face-disfigured-boyfriend-Daniel-Lynch.html
http://www.doobybrain.com/2010/12/15/photo-of-a-severe-acid-attack-victim/

_________________
Barbarus hic ego sum quia non intelligor illis (I am a barbarian to those who do not know me) Ovid


Top
iNow
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Mon Jun 11, 2012 2:53 pm
User avatar
Original Member
Original Member

Joined: Thu Aug 04, 2011 11:40 pm
Posts: 5729
Location: Iowa

Offline
I wonder if mississippichem is lurking... His would be a response that I both trust and likely understand. :)

_________________
iNow

"[Time] is one of those concepts that is profoundly resistant to a simple definition." ~C. Sagan


Top
DrRocket
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Tue Jun 12, 2012 2:39 am
Original Member
Original Member

Joined: Fri Aug 05, 2011 2:22 am
Posts: 477

Offline
jimmydasaint wrote:
I have seen the aftermaths of some horrific acid attacks on, mostly women (how mysoginistic is that?) from husbands or boyfriends. However, I wondered what it does to living tissue from a mechanistic point of view. Which molecules are damaged and how? Any ideas?

http://www.dailymail.co.uk/femail/article-1221077/Katie-Piper-Acid-attack-victim-bravely-shows-face-disfigured-boyfriend-Daniel-Lynch.html
http://www.doobybrain.com/2010/12/15/photo-of-a-severe-acid-attack-victim/


The usual reaction is a hydration reaction between, say sulfuric acid, and water. It is a highly exothermic reaction and that, combined with dehydration is the source of the tissue damage.

http://en.wikipedia.org/wiki/Sulfuric_a ... g_property

_________________
gone


Top
jimmydasaint
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Tue Jun 12, 2012 4:50 pm
User avatar

Joined: Fri Aug 12, 2011 4:53 pm
Posts: 380
Location: Farnham Royal, Bucks

Offline
DrRocket wrote:
jimmydasaint wrote:
I have seen the aftermaths of some horrific acid attacks on, mostly women (how mysoginistic is that?) from husbands or boyfriends. However, I wondered what it does to living tissue from a mechanistic point of view. Which molecules are damaged and how? Any ideas?

http://www.dailymail.co.uk/femail/article-1221077/Katie-Piper-Acid-attack-victim-bravely-shows-face-disfigured-boyfriend-Daniel-Lynch.html
http://www.doobybrain.com/2010/12/15/photo-of-a-severe-acid-attack-victim/


The usual reaction is a hydration reaction between, say sulfuric acid, and water. It is a highly exothermic reaction and that, combined with dehydration is the source of the tissue damage.

http://en.wikipedia.org/wiki/Sulfuric_a ... g_property


Thanks for the reply doc. So it is the equivalent of a burning reaction without a flame? The women in the OP had their lives destroyed by jealousy and spite. It is certainly a very horrific fate to suffer.

I wonder if quick acess to water could attenuate the worst symptoms?

_________________
Barbarus hic ego sum quia non intelligor illis (I am a barbarian to those who do not know me) Ovid


Top
marnixR
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Tue Jun 12, 2012 7:23 pm
User avatar

Joined: Thu Aug 04, 2011 8:35 pm
Posts: 4883
Location: Cardiff, Wales

Offline
if it's plenty of water then it might help - just a mere splash in the face wouldn't make much difference
what you need is something akin to a lab safety shower

Image

_________________
"Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
"Someone is WRONG on the internet" (xkcd)


Top
jimmydasaint
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Tue Jun 12, 2012 7:35 pm
User avatar

Joined: Fri Aug 12, 2011 4:53 pm
Posts: 380
Location: Farnham Royal, Bucks

Offline
marnixR wrote:
if it's plenty of water then it might help - just a mere splash in the face wouldn't make much difference
what you need is something akin to a lab safety shower

Image


That is similar to what I was thinking but, in a street situation, a bath full of water or rapid running water could be the solution.

_________________
Barbarus hic ego sum quia non intelligor illis (I am a barbarian to those who do not know me) Ovid


Top
DrRocket
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Wed Jun 13, 2012 4:39 pm
Original Member
Original Member

Joined: Fri Aug 05, 2011 2:22 am
Posts: 477

Offline
jimmydasaint wrote:
marnixR wrote:
if it's plenty of water then it might help - just a mere splash in the face wouldn't make much difference
what you need is something akin to a lab safety shower



That is similar to what I was thinking but, in a street situation, a bath full of water or rapid running water could be the solution.


That is the basic idea. What you are trying to do is to dillute the acid and cool the reaction very rapidly. The key is a LOT of water in short order, so if by rapid you mean high volume, as opposed to merely a high pressure jet then you have the right idea.

Unfortunately horse troughs are not usually readily available these days. If an open fire hydrant were available that would be just the ticket. Lacking that, any source of water in large volume, quickly, would help. The key is quickly, particularly if the eyes are involved.

Unfortunately there is very little that one could reasonable do to be prepared. Carrying around a vat of water or a large supply of baking soda is not practical.

This is really true of almost any form of violent attack. An attacker,say with a knife, withing twenty feet of someone is difficult to stop even if one is armed with a gun. To prevent or defend against an attack of sucha violent nature one is forced to maintain a high level of situational awareness, combined with some ability to thwart the attack. Weapons and martial arts are effective only if one has sufficient reaction time to employ them. Even extremely highly trained martial artists (I lhave, for instance, seen this guy up close in action and his speed is amazing http://en.wikipedia.org/wiki/Takayuki_Mikami) can be "sucker-punched" if they are caught unaware. But if one is aware of one's surroundings then one can usually take effective action to avoid a conflict or deal with it if one is truly unavoidable.

_________________
gone


Top
DrRocket
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Wed Jun 13, 2012 4:43 pm
Original Member
Original Member

Joined: Fri Aug 05, 2011 2:22 am
Posts: 477

Offline
jimmydasaint wrote:

Thanks for the reply doc. So it is the equivalent of a burning reaction without a flame?


That is part of it. The other part is that the reaction dehydrates the cells when it reacts with water.

Of course, a flame also effectively dehydrates cells when it causes the water in them to boil and evaporate.

_________________
gone


Top
iNow
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Thu Jun 14, 2012 4:42 am
User avatar
Original Member
Original Member

Joined: Thu Aug 04, 2011 11:40 pm
Posts: 5729
Location: Iowa

Offline
DrRocket wrote:
This is really true of almost any form of violent attack. An attacker,say with a knife, withing twenty feet of someone is difficult to stop even if one is armed with a gun. To prevent or defend against an attack of sucha violent nature one is forced to maintain a high level of situational awareness, combined with some ability to thwart the attack. Weapons and martial arts are effective only if one has sufficient reaction time to employ them. Even extremely highly trained martial artists (I lhave, for instance, seen this guy up close in action and his speed is amazing http://en.wikipedia.org/wiki/Takayuki_Mikami) can be "sucker-punched" if they are caught unaware.

Separate, but related... Did you happen to catch Mythbusters this past weekend? They tested the idea, "Never bring a knife to a gun fight" and had some fun results.

On the latter point about "being caught unaware," that is actually a strong reason why packs/tribes/and groups became so helpful evolutionarily. Instead of having just two eyes and two ears, when we are in a pack or a group we effectively "borrow" the eyes and ears of those around us... and those eyes and ears can look and listen in all different directions at once and sound warning calls when danger approaches. Meerkats at notorious for this behavior.

Back OT, though... What I've taken away from the above is that acid basically uses the components of skin and muscle cells in ways that they're not intended, and it breaks them down rapidly like acetone on styrofoam... ultimately unzipping your cells chemically. I know it lacks precision, but is that a fair summary?

_________________
iNow

"[Time] is one of those concepts that is profoundly resistant to a simple definition." ~C. Sagan


Top
DrRocket
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Sun Jun 17, 2012 5:29 am
Original Member
Original Member

Joined: Fri Aug 05, 2011 2:22 am
Posts: 477

Offline
iNow wrote:
Separate, but related... Did you happen to catch Mythbusters this past weekend? They tested the idea, "Never bring a knife to a gun fight" and had some fun results.



I did not see Mythbusters. However, there are much more definitive sources of data for this problem and the the issue of a gun vs a knife is a standard topic in self-protection. It is well-known that a holstered gun is not a good defense against a knife once the knife weilder is within about 7 yards of the person with the gun.

On the other hand, if the armed defender is skilled and recognizes the threat from the knife in a timely fashion (before the attacker closes to within about 21 feet) the guy with the knife is toast.

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

_________________
gone


Top
imp
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Thu Aug 01, 2013 6:47 am

Joined: Thu Aug 01, 2013 5:50 am
Posts: 55

Offline
If one dumps a bit of conc. acid, say, hydrochloric, onto the soil, many might think "what a damn polluter!". What really happens, though, with all that fizzing and foam, is that the HCl simply attacks the compounds which it likes best in that soil, creating salts where before there was basic stuff having relatively high Ph. Not much harm done, in one's garden area. It kills plants, though, reacting similarly with their juices.

The BEST display of "acid power" is to obtain a sturdy bottle, beer bottle is perfect (!), pour in about 50cc water, add 50 cc hydrochloric acid, have a toy party balloon ready, drop a hunk of reactive metal into the bottle (I used my Dad's zinc strip off the wallpapering stuff he had) merely a fingernail-sized piece, immediately squipe the balloon over the neck, and watch it fill with hydrogen gas. Pinch it off before it's too formidably inflated, tie it off, and secure it to a reasonably immovable object.

When this hydrogen inflated balloon is approached with a stick, maybe 2-3 feet long, having a lit match secured to it's end, the balloon will most rewardingly release it's hydrogen as it combines with oxygen in the air, creating an amazing flash and report!

I did this in my Math class, as a sort of deterrent against their daily apathy. Within 5 minutes, my boss, the Principal, showed up, exclaiming they had in the offices felt the building shake! I shrugged, the class (young adults) loved it! The boss asked what we had done: I told him "We created water!".

_________________
Testing the waters is an old trick. Drowning in them might result.


Top
jimmydasaint
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Thu Aug 01, 2013 7:18 pm
User avatar

Joined: Fri Aug 12, 2011 4:53 pm
Posts: 380
Location: Farnham Royal, Bucks

Offline
wonderful experiment! In Maths class? At least you could have asked them about reacting volumes of acid and metal compared to number of moles of gas produced:)

However, I like the approach. The only problem is where to get hold of hydrochloric acid.

_________________
Barbarus hic ego sum quia non intelligor illis (I am a barbarian to those who do not know me) Ovid


Top
marnixR
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Thu Aug 01, 2013 7:51 pm
User avatar

Joined: Thu Aug 04, 2011 8:35 pm
Posts: 4883
Location: Cardiff, Wales

Offline
get friendly with someone who works in a steel plant at the pickle lines (they'll either use hydrochloric or sulphuric acid to pickle the steel clean)

_________________
"Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
"Someone is WRONG on the internet" (xkcd)


Top
imp
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Fri Aug 02, 2013 3:54 am

Joined: Thu Aug 01, 2013 5:50 am
Posts: 55

Offline
Concentrated HCl is widely available here in the States, sold as "pool acid", used to bring down high Ph resulting from degradation of water by chlorination.

I find it hard to believe one cannot buy it in UK. Now, nitric acid, I could understand restrictions on. imp

_________________
Testing the waters is an old trick. Drowning in them might result.


Top
marnixR
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Fri Aug 02, 2013 6:18 am
User avatar

Joined: Thu Aug 04, 2011 8:35 pm
Posts: 4883
Location: Cardiff, Wales

Offline
i suppose it depends on the quantities - a lab bottle is probably OK, industrial quantities not

_________________
"Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
"Someone is WRONG on the internet" (xkcd)


Top
imp
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Fri Aug 02, 2013 5:53 pm

Joined: Thu Aug 01, 2013 5:50 am
Posts: 55

Offline
Our local supermarket has a display of perhaps 50 one-gallon bottles of concentrated HCl, no limits on purchase quantity. Across the street is another similar, gigantic competing store......

_________________
Testing the waters is an old trick. Drowning in them might result.


Top
iNow
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Fri Aug 02, 2013 7:02 pm
User avatar
Original Member
Original Member

Joined: Thu Aug 04, 2011 11:40 pm
Posts: 5729
Location: Iowa

Offline
It's quite possible that (as you mentioned above) things are different in the US than in the UK... and potentially even different between states within the US.

Jimmy - Is this the type of experiment you might consider doing in your classes?

_________________
iNow

"[Time] is one of those concepts that is profoundly resistant to a simple definition." ~C. Sagan


Top
imp
Post  Post subject: Re: What Damage Can a Concentrated Acid Do?  |  Posted: Fri Aug 02, 2013 10:46 pm

Joined: Thu Aug 01, 2013 5:50 am
Posts: 55

Offline
One need not use concentrated acid, but something like vinegar, 3% or whatever it is, would react so slowly as to be impractical. 50% acid would be much safer, maybe even 25%. Using HCl and Zinc, leaves Zinc Chloride behind in the bottle, and unreacted acid, unless proportions are exact, nothing very toxic at all.

The hydrogen gas generated likes to burn violently, explosively, with the air, but only if ignited. The shreds of balloon remaining after "making water", are found to be covered liquid water, the remainder dispersed as water vapor.

I somehow learned to do this as a kid, using my Mother's kitchen gas stove. The balloon placed on a grate, the gas valve turned on and hastily backing away, it always took several seconds for the pilot to ignite the burner, plenty of time to retreat. The report is more like a loud "WHUMP", than explosion, though she claimed the house reverberated with it. This was not a popular thing with her!

_________________
Testing the waters is an old trick. Drowning in them might result.


Top
Display posts from previous:  Sort by  
Print view

Who is online
Users browsing this forum: No registered users and 0 guests
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
Jump to:   
cron

Delete all board cookies | The team | All times are UTC


This free forum is proudly hosted by ProphpBB | phpBB software | Report Abuse | Privacy