# Logic problem

I heard this problem a few months ago:
James Bond swam underwater to get into the villain's base. When he arrived, he was discovered and placed in a vat of very strong acid, how did he survive?

1) What kind of acid?
2) Was he wearing anything, or inside of anything, that prevented direct contact with the acid?
3) Is the answer you're looking for actually physically plausible?

You'd be surprised how many people actually die (or are seriously injured) by falling into vats of acid. Here are a few:

http://www.freerepublic.com/focus/f-news/1689446/posts
http://www.birminghammail.net/news/...y-nine-falls-into-vat-of-acid-97319-23406773/
http://www.examiner.com/a-951852~Teen_falls_into_vat_of_toxic_chemical__dies.html
http://www.expressandstar.com/2006/11/27/horror-as-man-falls-into-acid/ [Broken]

From these reports it's apparent that falling into a vat of acid is not necessarily fatal if you can manage to get back out in time and wash off. So a possible solution to the Bond crisis is that he simply does that. If ht was put into a glass vat, then maybe he escapes by using his P99 to shoot his way out.

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1. Something very strong which can kill a person- something highly concentrated..
2. The only clothing he was wearing was a wetsuit, which would not have protected him, as it is not waterproof.
3. Yes, theoretically.

Let's say he couldn't get out and was in there for a long time.

1. Something very strong which can kill a person- something highly concentrated..
2. The only clothing he was wearing was a wetsuit, which would not have protected him, as it is not waterproof.
3. Yes, theoretically.

Let's say he couldn't get out and was in there for a long time.

4) Did his wetsuit actually come into contact with the acid?
5) Did his skin actually come into contact with the acid?
6) Was his wetsuit treated in any way?
7) How much time transpired between him getting out of the water and getting put into the acid?
8) How much time did or could his suit spend in contact with the acid? (assuming it did at all)
9) Was he hurt in any way? (The implication from the wording is that he was totally fine)
10) Was anything else apart from him placed into the acid either shortly before, during, or shortly after his submersion? (Assuming he was actually submersed, which isn't explicitly stated, see #4 and #5)

DaveE

4. Technically yes
5. "
6. No
7. Not very long
8. Say, 20 minutes.
9. He was unhurt
10. He was submerged, but nothing apart from him and what he had with him went in the acid

Can I also point out that the quantity of acid was just enough to submerge him.

7. Not very long

My guess here (and I'm not up on the chemistry, really) is that there's something about the fact that his suit is still wet that's going to help him out. If (say) it was salt water versus fresh water, that may have an effect on the acid-- especially given that you stated that it was just sufficient to submerge him, which was going to be another question. IE, are we talking a 3 meter diameter cylindrical vat of acid that's 3 meters deep, or if it's JUST big enough to submerge him fully. Sounds like the latter, meaning there's not as much acid to neutralize.

DaveE

come on here...he swam in to the villain's BASE..thus neutralizing the ACID bath...a base is tyically sticky so provided him with a neutralizing coating despite being submerged in acid

come on here...he swam in to the villain's BASE..thus neutralizing the ACID bath...a base is tyically sticky so provided him with a neutralizing coating despite being submerged in acid

Very good, but not the answer I was looking for.

Perhaps I should have used 'lair'.

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My guess here (and I'm not up on the chemistry, really) is that there's something about the fact that his suit is still wet that's going to help him out. If (say) it was salt water versus fresh water, that may have an effect on the acid-- especially given that you stated that it was just sufficient to submerge him, which was going to be another question. IE, are we talking a 3 meter diameter cylindrical vat of acid that's 3 meters deep, or if it's JUST big enough to submerge him fully. Sounds like the latter, meaning there's not as much acid to neutralize.

DaveE

That's not what I was thinking of.
Although I'm also not that up on the chemistry, I don't think that being in salt water would help to neutralise the acid, as sodium chloride is not a base. If you're thinking it might dilute the acid, there's still quite a lot of acid there.

Wetsuits typically retain water in a boundary between the rubber and skin...this could have afforded him protection assuming he moved into the vat fairly quickly

There was enough time to get water under the wetsuit.

There was enough time to get water under the wetsuit.

yes, I'm saying that that water layer protected him once he went into the vat of acid

come on here...he swam in to the villain's BASE..thus neutralizing the ACID bath...a base is tyically sticky so provided him with a neutralizing coating despite being submerged in acid
You wouldn't want to be there when the base neutralizes the acid.

yes, I'm saying that that water layer protected him once he went into the vat of acid

But a wetsuit isn't watertight. Anyway, his face would have been exposed, and that would have seriously harmed him, and may well have killed him.

C'mon, this is James Bond we're talking about. None of those slow painful death things is ever going to work against him.

Thinking quickly, he turned on the magnet in his watch which pulled his keychain out of his tux jacket lying on a chair on the other side of the room. On the keychain is a remote controller for his Austin Martin which he backs up in order to have room to pick up speed and for special effect. He then rushes the car forward crashing into the building, tipping over the vat and turning the tables on the bad guys who now wish they had just shot him between the eyes with a .45 like anyone, Mahatma Gandhi included, knows they should have. He makes a pun based on the way they died, "looks like they failed the acid test" or something like that, gets the champaign and caviar out of the glove compartment, and makes love to the beautiful woman who was chasing these idiots to get revenge for killing her third cousin twice removed, the only crime they ever pulled off successfully.

Maybe it's something to do with the breathing apparatus he used, maybe the oxygen cannisters? But I've no idea how oxygen and acid would react...

Maybe it's something to do with the breathing apparatus he used, maybe the oxygen cannisters? But I've no idea how oxygen and acid would react...

There's a good question-- it says "wetsuit", which I interpreted to mean "wetsuit, and wetsuit only", but typically there's a lot of associated diving gear such as a mask, air tanks, weights, fins, snorkel, etc. Plus it's James Bond, who always has a wide range of other assorted gear like camera pens, pistols, arsenic, and so forth.

Also, earlier, the reply was "nothing apart from him and what he had with him went in the acid", which given the phrasing implies that there was something else he took with him into the acid apart from his normal body (no gadgets, etc implanted), and a material that covered perhaps 95% of his skin.

As far as I can tell, his face is directly exposed to the liquid that's in the vat (that's almost explicitly stated). Hence, by the time his face hits the liquid, the liquid can no longer be a strong acid (or else he's harmed, even slightly). So something has happened to the acid to reduce its strength (or turn it into some other liquid) before he's completely submerged.

The only ways to do that would be to add some other agent (ha-ha!) to the liquid, which Bond either has with him or somehow is added otherwise.

DaveE

I had the thought that maybe the air tanks would offer enough buoyancy so that he floated on the surface, but then that wouldn't fit with being submerged, or perhaps it would as when he's thrown in he would probably be submerged for a short time before bobbing up, and surely that would be enough to injure him.

Looking at post #5 the acid is just enough to submerge him so there's probably not enough acid anyway. But what if he's thrown in with sufficient velocity that all the acid splashes up out of the vat? I'm thinking maybe Archimedes principle or something similar might come into play, with him displacing his body weight (or volume?) in acid or something along those lines?

EDIT. But then the wet suit wouldn't have spent 20 minutes in contact with the acid unless you count the soaked up acid from the initial contact.

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Maybe it's something to do with the breathing apparatus he used, maybe the oxygen cannisters? But I've no idea how oxygen and acid would react...

You're on the right lines there.

I heard this problem a few months ago:
James Bond swam underwater to get into the villain's base. When he arrived, he was discovered and placed in a vat of very strong acid, how did he survive?

Um...the vat wasn't full?

i) Is the fact it is James bond important?
ii) Is any knowledge of chemistry required?
iii) Is the acid still an acid afterwards?

i) Not really, no.
ii) Probably a little.
iii) No

Regular wetsuit?:

http://www.simplyscuba.com/xxGetImage.aspx?StockID=35605&ImageNumber=2 [Broken]

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OK, he would have used breathing apparatus to swim underwater- but what gives away the position of a diver using conventional breathing apparatus? How could this problem be overcome?

He could balance on the oxygen tank to keep himself out of the acid, which was after all just barely enough to have submerged him originally

OK, he would have used breathing apparatus to swim underwater- but what gives away the position of a diver using conventional breathing apparatus? How could this problem be overcome?

I assume you mean what gives away the position of a diver to observers on the water's surface? I assume you're referring to exhalation gas bubbles that float to the surface. In order to overcome that, you'd have to prevent the gas from escaping, and re-compress it so that it wouldn't bring you to the surface. So you'd need a contraption that sucks in your exhaled gas and re-pressurizes it in some sort of secondary tank. Either that, or you'd need a system that would transform the gas you breathe out into something else-- either another reasonably clear liquid, or something that's of reasonably equal density to water.

So, to be clear, I think everyone here is looking for a nice MacGyver-type solution. IE, something that you yourself could do if you had a normal run-of-the-mill diving suit, and were about to be tossed into a vat of acid. I just want to make sure we're not talking about some sort of super-high-tech device that nobody's ever heard of but is theoretically possible, or is available only to special military operatives, but James Bond just happens to have with him that somehow neutralizes acid.

DaveE

It is a device which is commercially available, and is in general use by divers. I don't think it's that obscure.

I did a little research and came up with a device known as a rebreather. It scrubs the carbon dioxide from exhaled air and adds oxygen. As a result, fewer bubbles are emitted. In order to perform this alchemy, sodium peroxide, a strong base, is used. I expect that if you took the sodium peroxide and mixed it with the acid, then harmless water would be created from the explosion. I wouldn't expect Bond to talk, I would expect him to die.

That's what I was looking for, although I think it would probably be calcium hydroxide as the main active ingredient.
What if, as he was being lowered into the acid, he broke open the rebreather and dropped it, with him being high enough up to survive.

That's what I was looking for, although I think it would probably be calcium hydroxide as the main active ingredient. What if, as he was being lowered into the acid, he broke open the rebreather and dropped it, with him being high enough up to survive.

How much calcium hydroxide is in your typical rebreather? If it's not a catalyst-style reaction (which I assume it isn't since you're just mixing acids and bases), wouldn't you need roughly the same amount of calcium hydroxide to neutralize the acid? I'm not big into chemistry, but how basic is calcium hydroxide? Would it be enough to really balance out a vat that's full of acid?

Let's make a guess, here-- in order to drop him in, tank and all, the diameter of the vat is going to be at least 3-4 feet in diameter. Probably more. And it's stipulated that it's enough to just BARELY submerge him, so when he jumps in, we can assume that the height of the acid is about 6 feet. So that's at a minimum 1.52*pi*6 cubic feet of volume (42 cubic feet), minus however much volume Bond and his suit take up.

I found one approximation that takes the normal mass and gets a rough approximation of human volume by dividing by 0.001kg/cm3. That would make Bond probably just shy of 3 cubic feet (that sounds a little small to me, but maybe not). And another few feet for his clothes and gear. So we're talking about no more than 10 cubic feet of volume for Bond and his equipment. Hence, it's a good bet that there's at least 30 cubic feet of acid to neutralize.

I'm guessing unless the calcium hydroxide reaction is catalytic (and it sounds like it isn't), there's NOT going to be enough to neutralize the acid.

DaveE

Well, the CO2 'scrubber' is made up of a variety of ingredients, although calcium hydroxide is the main ingredient. There is often some sodium hydroxide in there aswell, but I don't know what else there is- perhaps one of those could act as a catalyst.
Anyway, is your argument that there wouldn't be enough, or that the reaction wouldn't happen fast enough, because if it's the former, a catalyst won't help.

Please bear in mind that I didn't come up with this question first.

Anyway, is your argument that there wouldn't be enough, or that the reaction wouldn't happen fast enough, because if it's the former, a catalyst won't help.

Well, if it is a catalytic reaction (I assume it isn't? I don't honestly know), then yes, it'll take time, but how much time he's got isn't really stipulated in the problem. Maybe he gets the evil character to confess the whole evil plot before dropping Bond into the acid, and he winds up getting a half an hour before he's dropped into the vat. I guess you've got a potential issue there as well with the liquid stagnating (which would slow the reaction, I think?), but maybe he could drop his oxygen tank in completely (while opened slightly) so that the liquid would be more agitated and help continue to maximize the catalytic reaction's speed.

But really, I'm assuming that the reaction ISN'T a catalytic one, so that the calcium hydroxide is consumed as it neutralizes the acid. In which case, the question is, would there be sufficient calcium hydroxide to neutralize the acid to the point where it's bearable for Bond to submerge for the given 20 minutes or so?

I don't have any clue how much there is in your typical rebreather, but my Spidey-sense tells me there isn't enough. My off-the-wall guess is less than a 1 liter bottle's worth (probably less than a soda can's worth). And that's about 0.035ft3 (dunno why I picked cubic feet, but I'll go with it).

I have no idea what the minimum you'd need would be (I'm just pulling "best case" numbers out of the air here), but we do have a guess at the lower-bound amount of acid that needs to get neutralized, and that's roughly 30ft3 (see above post). So let's assume (best-case) that 1 cm3 of calcium hydroxide can neutralize 10 cm3 of the acid (I'm also assuming that volume relates to number of moles and so forth, so this is horrifically bad estimation, but it's all I've got at the moment.) If that's even modestly close to an upper bound for how much acid can be neutralized, you'd need about 3ft3 of calcium hydroxide to neutralize the acid, which sounds like WAY too much to me for him to have in his rebreather apparatus.

But, hey, I'm no chemist-- my last chemistry course was intro-level chemistry some 11 years ago. But my "common-sense" test tells me that even stretching the plausibility, it sounds like it's not even close to possible. So I'm asking if you happen to know any more details, since I could be way off. I don't know the answer, but I'm sure if we can find out roughly how much calcium hydroxide is in your average rebreather, SOMEBODY on the PF will probably be able to tell us how plausible this whole thing is.

DaveE

Well, unfortunately, this puzzle sucks since there's no real world solution

Well, if it is a catalytic reaction (I assume it isn't? I don't honestly know), then yes, it'll take time, but how much time he's got isn't really stipulated in the problem. Maybe he gets the evil character to confess the whole evil plot before dropping Bond into the acid, and he winds up getting a half an hour before he's dropped into the vat. I guess you've got a potential issue there as well with the liquid stagnating (which would slow the reaction, I think?), but maybe he could drop his oxygen tank in completely (while opened slightly) so that the liquid would be more agitated and help continue to maximize the catalytic reaction's speed.

But really, I'm assuming that the reaction ISN'T a catalytic one, so that the calcium hydroxide is consumed as it neutralizes the acid. In which case, the question is, would there be sufficient calcium hydroxide to neutralize the acid to the point where it's bearable for Bond to submerge for the given 20 minutes or so?

I don't have any clue how much there is in your typical rebreather, but my Spidey-sense tells me there isn't enough. My off-the-wall guess is less than a 1 liter bottle's worth (probably less than a soda can's worth). And that's about 0.035ft3 (dunno why I picked cubic feet, but I'll go with it).

I have no idea what the minimum you'd need would be (I'm just pulling "best case" numbers out of the air here), but we do have a guess at the lower-bound amount of acid that needs to get neutralized, and that's roughly 30ft3 (see above post). So let's assume (best-case) that 1 cm3 of calcium hydroxide can neutralize 10 cm3 of the acid (I'm also assuming that volume relates to number of moles and so forth, so this is horrifically bad estimation, but it's all I've got at the moment.) If that's even modestly close to an upper bound for how much acid can be neutralized, you'd need about 3ft3 of calcium hydroxide to neutralize the acid, which sounds like WAY too much to me for him to have in his rebreather apparatus.

But, hey, I'm no chemist-- my last chemistry course was intro-level chemistry some 11 years ago. But my "common-sense" test tells me that even stretching the plausibility, it sounds like it's not even close to possible. So I'm asking if you happen to know any more details, since I could be way off. I don't know the answer, but I'm sure if we can find out roughly how much calcium hydroxide is in your average rebreather, SOMEBODY on the PF will probably be able to tell us how plausible this whole thing is.

DaveE

I don't know- I'm not a chemist. I just heard this problem somewhere.

Ca(OH)2+(say)H2SO4->2H20+CaSO4

I'm still unsure about how much acid there would be or how much there would be in the rebreather. To be honest, when I heard this, I didn't really go into the answer in as much detail as you obviously want from me.

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