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Science

A Water Molecule's Chemical Formula Isn't Really H20 103

Posted by timothy from the at-least-not-all-the-time dept.
hackwrench writes "According to this article in Physics News Update, a water molecule's chemical formula is really not H2O, at least from the perspective of neutrons and electrons interacting with the molecule for only attoseconds (less than 10-15 seconds). According to new and recent experiments, neutrons and electrons colliding with water for just attoseconds will see a ratio of hydrogen to oxygen of roughly 1.5 to 1, so a more accurate formula for water under these circumstances would be H1.5O."
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A Water Molecule's Chemical Formula Isn't Really H20 More

A Water Molecule's Chemical Formula Isn't Really H20

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  • Good thing I never paid attention in high school chemistry, or I'd be all confused now... ;)

    H20, H1.5O, HwhateverO. It still tastes great!

  • Question. (Score:4, Insightful)

    by sporty ( 27564 ) on Sunday August 03, 2003 @08:03PM (#6602356) Homepage
    Isn't H1.5O illegal nomenclature? Shouldn't it be 2H30? Mabe cp30?

    • Re:Question. (Score:2, Interesting)

      by Malcolm Scott ( 567157 )
      Or perhaps you mean H3O2. But anyway, it's all quantum, so we may well be talking about half-atoms floating round.....
    • Shouldn't it be 2H30? Mabe cp30?

      no, that looks like 2 molecules with 3 hydrogen and one oxygen atom each, wich doesn't really make any sense.
      i guess what you mean is H302, which wouldn't be right either, but would (apperently) have the right proportion of hydrogen and oxygen atoms
      • See.. this is why i'm just a stupid software architect. Stupid chemistry. Bah! :)

      • Re:Question. (Score:4, Informative)

        by twiztidlojik ( 522383 ) <dapplemac@m[ ]com ['ac.' in gap]> on Monday August 04, 2003 @12:19AM (#6603596) Homepage
        Actually, the hydrinuim ion, or H3O+, is an H3O. Technically, 2H3O+ would mean two hydronium ions.

      • Re:Question. (Score:3, Insightful)

        by Sgt York ( 591446 )
        2H3O? H3O2? H6O3.1416?

        That's what you get when two fields collide like this. H2O is a stoichiometric formula, it's not supposed to represent the actual molecule at all times. If the ratio for water was actually 3:2 instead of 2:1, fuel cells (like on US space missions) would wind up with an excess of hydrogen after reaction. That has not been observed. Also, if you electrolyze water, you get a 2:1 molar ratio of H to O. Not a 3:2 ratio.

        If yu take pure water, you will not find a homogeneous mixture of molecu

        • If the ratio for water was actually 3:2 instead of 2:1, fuel cells (like on US space missions) would wind up with an excess of hydrogen after reaction. That has not been observed.

          Don't you mean a deficit of hydrogen? 3/5 is less than 2/3

    • Mabe cp30?

      It can't be that, since water doesn't contain phosphorus.

      C3PO:


      C

      |

      C = C - P = O

    • Re:Question. (Score:4, Interesting)

      by fm6 ( 162816 ) on Sunday August 03, 2003 @09:48PM (#6602937) Homepage Journal
      To a chemist, maybe. To a physicist there's nothing abusrd about saying "half an oxygen atom" or "50% chance of interacting with an oxygen atom".

      Well, I exaggerate. But you got to admit that modern physics is really weird.

    • Re:Question. (Score:2, Informative)

      by Anonymous Coward
      There are lots of compounds where they have to express them as fractions, mainly because the exact structure is more of a solid-solution-substitution rather than a hard and fast ratio (pyrrhotite is one, "Fe1-xS"). That's more something you see in Geology rather than chemistry though, since nature is a lot more disordered than chemists in labs.
      • unless you're a chemist in a lab making high temperature superconductors... many inorgangic solids that are studied for superconductivity have fractional formula notation.
    • You're right that 'H1.5O' is "illegal" nomenclature, it would really be 'H3O2', because chemists like whole numbers. This sort of flies in the face of everything I learned in highschool, though.

    • Re:Question. (Score:3, Interesting)

      by Dahan ( 130247 )
      It's not illegal per se... see the definition of non-stoichiometric [wordreference.com]. One of the first high-temperature superconductors has the formula YBa2Cu3O7-d (d should be a lowercase delta), where d is a small number, so you end up with something like YBa2Cu3O6.95 or YBa2CU3O6.7. However, In this particular case, I think saying that water is like H1.5O is incorrect, or at least misleading.
    • If what you meant was two hydrogen and three oxygen then no that would not be correct since that would be a single molecule with the components of two water molecules. But if you said 2H3O2 then my offices consensus(sp) is that that'd be two molecules with a total of three hydrogen atoms and two oxygen atoms between em.

  • Still water! (Score:5, Funny)

    by trompete ( 651953 ) on Sunday August 03, 2003 @08:08PM (#6602381) Homepage Journal
    Well, as long as it's still wet, there's no reason to panic.
  • is now H2O.99999999

    • Re:water in time (Score:5, Funny)

      by Creepy Crawler ( 680178 ) on Sunday August 03, 2003 @09:21PM (#6602779)
      And if it was H2O.99999973 , we'd know what CPU they used to count it with....

      • Re:water in time (Score:4, Insightful)

        by macemoneta ( 154740 ) on Monday August 04, 2003 @05:49PM (#6609935) Homepage
        > And if it was H2O.99999973 , we'd know what CPU they used to count it with....

        This was a funny, but it's also very true. People forget that the instrumentation used is also subject to error. I once spent a day hunting down a network problem, only to realize that the test equipment was creating the error, not the equipment under test. All the same model equipment from that manufacturer had the flaw, which we proved with test equipment from two other manufacturers.

  • Can you say WRONG (Score:5, Interesting)

    by MarkusQ ( 450076 ) on Sunday August 03, 2003 @08:26PM (#6602483) Journal

    Bah! The interpretation given this research is absurd. If I invented a new machine to count the legs on cows, and my machine said that typical cows had three legs each, what would we conclude? That we'd been wrong about cows all these years, or that my machine wasn't working quite the way I'd expected it to?

    In the present case, a better headline would have been something like "Unexpected effect hides some protons in neutron & electron scattering experements."

    -- MarkusQ

    • Maybe they used an old Pentium processor...

      =Smidge=

    • Re:Can you say WRONG (Score:5, Insightful)

      by OwnerOfWhinyCat ( 654476 ) * on Monday August 04, 2003 @12:30AM (#6603636)
      Must agree Markus. The cow leg counter is a great example.

      The absurdity in the article makes one wonder where we've been getting all that hydrogen from for all these years. We've been cracking H2O with electrolysis and been getting both H's pretty consistently for decades. The experiments that show the PH are pretty solid as well, so it seems a little early to start theorizing that black holes are giving off the extra half a mole of Hydrogen we've been getting out of a mole of water.

      The cool part (that they seemed to entirely miss) is that these techniques could be used to confirm/reject models for wave-theory covalent bonding. Maybe that tough little benzene ring is resonant at more than just the electron shell level....
    • Your second grade teacher may have taught you that water is H20, but she neglected to mention that water is in an equilbrium between H20 and H + OH. Its typically thought that the coefficient of seperation of water is pretty insigifnicant, along the lines of 10^-14.

      Meaning that if the water has a pH of 7 then we should be expecting something closer H1.999O. If the difference is flawed experimentation, I would expect proper scientific reserarch to explain this, just as I'd expect it to explain the reasons t

      • Meaning that if the water has a pH of 7 then we should be expecting something closer H1.999O.

        No, we should expect to find a mix of H2O, H, and OH. In any macroscopic volume the ratio between H & O should be 2, not 1.999 or even 1.9999999. The pH shouldn't even enter into it (if the H+'s collectively wandered a macroscopic distance from the OH-'s, water would be incredibly dangerous).

        Remember, they were looking at the H's & O's via p + n & p + e scattering.

        -- MarkusQ

    • I want my 4th cow leg back. Make your sadistic machine give it back to me.

      -n

    • Re:Can you say WRONG (Score:2, Informative)

      by OG ( 15008 )
      Your interpretation of the article is absurd (if you even read it). The H1.5O thing was a hook to get you to read it. No one seriously suggested that water only had 1.5 hydrogen atoms.

      From the article: "Apparently, the protons in hydrogen were sometimes "invisible" to the neutron probes. While the exact details are still being debated by theorists, the researchers' own theoretical considerations suggest the presence of short-lived (sub-femtosecond) entanglement, in which protons in adjacent hydrogen atom

      • Re-read my post. I didn't offer an "interpretation of the article" (which I did read before posting). I said that interpretation of the article and headline posted on slashdot (which, I might point out, someone else submitted to slashdot) was absurd. You may be right in thinking it was a "hook" to get people to read the article; I know such tactics are common in tabloid journalism and in movie adverts. That doesn't mean that it wasn't absurd.

        -- MarkusQ

        • First of all, the slashdot article title is the same as the original article title on the "Physics News Update" website. It's not just a tabloid tactic. It's standard in anything but bonafide journals (scientific, legal, what-have-you), and sometimes even there. The creator of the title assumes the reader is intelligent enough to realize that something more is going on.

          As to the Slashdot article itself, the submitter made sure to use terms like "from the perspective of" and "under these circumstances".

    • RTFA (Score:4, Informative)

      by Mt._Honkey ( 514673 ) on Monday August 04, 2003 @05:01PM (#6609528)
      If you would have RTFA before posting, you would know that they aren't saying that at all.
      While the exact details are still being debated by theorists, the researchers' own theoretical considerations suggest the presence of short-lived (sub-femtosecond) entanglement, in which protons in adjacent hydrogen atoms (and possibly the surrounding electrons) are all interlinked in such a way as to change the nature of the scattering results. Realizing that water itself has anomalous properties, the researchers repeated the neutron experiments in other more typical molecules, for instance in benzene (conventionally noted as C6H6). In that case, they found that the neutrons saw a ratio of hydrogen to carbon of 4.5 to 6! Meanwhile, this effect was also confirmed in various hydrogen-containing metals, in a collaboration with Uppsala University in Sweden.
      They are saying that maybe at attosecond time scales, maybe the adjacent hydrogen nuclei are entangled in such a way that fewer of them interact with the incoming particle, or something to that effect. To fully understand this probably requires a deeper knowlege of quantum mechanics and more detail than this article provides, but it is not without precident for many particles to behave as one. Check out Bose-Einstein condensates for info on that.

      • And if you had read my post, you would have noticed that I was making the same point you are, specifically that the headline and blurb were totatally absurd and unrelated to the research. To recap:
        1. Someone did some research
        2. Someone else posted an article on slashdot, totally misrepresenting the research.
        3. I posted a comment, pointing out that the article on slashdot was an absurd misrepresentation of the research, and suggesting a better headline.
        4. You replied to my comment, telling me to RTFA and quoting
        • Sorry, but reading your comment it seemed like you were talking about the research itself and dismissing it out of hand.
    • The point of the letter isn't so much that your four-legged cow only has 3 legs, but that there is some interesting effect whereby it seems to have 3 legs, at least when relying on time-scales as short as attoseconds, and particles such as neutrons and electrons, as opposed to photons.

      The original poster seems to imply the experiments were performed on a femtosecond time-scale (10^-15) as opposed to the attosecond (10^-18). The confusion may come from the fact that the article says something about probing

  • It's a scam (Score:3, Funny)

    by Frac ( 27516 ) on Sunday August 03, 2003 @08:26PM (#6602485)
    Of course it's wrong! Now they'll have to update all the chemistry textbooks, and of course all the old editions will be worthless now. Ah HA!

    What they don't tell you is that they got a bunch of other "corrections" under their sleeve. You know, because in a year or so they're going to need another excuse to roll out a new edition.

    Quite similar to Microsoft's "pay us to upgrade, so you can patch up the bugs we created in the first place!" biz model, actually. ;-P

  • Scientist to struggling chemistry students... (Score:4, Funny)

    by quandrum ( 652868 ) on Sunday August 03, 2003 @08:28PM (#6602501)
    Just kidding!
  • Clearly their test samples were contaminated with dihydrogenmonoxide.

  • No single instant of time (Score:4, Informative)

    by SpaceLifeForm ( 228190 ) on Sunday August 03, 2003 @09:10PM (#6602708)
    That should be 10^-15 seconds, not 10-15 seconds.

  • Lower interaction rate, not fewer atoms. (Score:5, Insightful)

    by Christopher Thomas ( 11717 ) on Sunday August 03, 2003 @09:19PM (#6602767)
    The spin in the article is misleading. What's actually happening is that the interaction cross-section between electron and neutron beams and the hydrogen in water (and in things like hexane) is lower than expected relative to the interaction cross-section with oxygen or carbon.

    The conjecture about why the phenomenon occurs (entanglement of protons) is interesting, but they're going to need to find a plausible mechanism and confirm that it's happening before we really know what's going on.

  • H-2-WHOA!! (Score:5, Funny)

    by quinkin ( 601839 ) on Sunday August 03, 2003 @09:29PM (#6602832)
    But that will mess-up up the name of the waterslide in the Simpsons...

    H-2-WHOA!

    Q.

  • Change water all you want (Score:5, Funny)

    by 1nv4d3r ( 642775 ) on Sunday August 03, 2003 @10:34PM (#6603161)
    H-2-0, H-3-0, H-1.5-0 I don't care.

    But consider yourselves warned: Leave my caffeine molecule alone!

  • By my references... (Score:5, Informative)

    by chriso11 ( 254041 ) on Sunday August 03, 2003 @10:57PM (#6603265) Journal
    Actually, an attosecond is 10e-18, not 10e-15. 10e-15s would be a femtosecond (and 10e-12 is a picosecond). Yes, I know that they say an attosecond is 'less than 10e-15sec', but it is misleading.

    • Re:By my references... (Score:2, Interesting)

      by jgoemat ( 565882 )
      I agree it is a little misleeding how they say it, but they do say in the 100-500 attosecond range, which is less than 10e-15 (0.1 to 0.5 * 10e-15) and close enough to say "less than 10e-15" and get the point across...

    • Re:By my references... (Score:3, Informative)

      by ggwood ( 70369 )
      Here is the list of "some" prefixes from Serway & Jewitt (Principles of Physics 3rd Ed.)

      Power Prefix Abbreviation
      -24 yocto y
      -21 zepto z
      -18 atto a
      -15 femto f
      -12 pico p
      -9 nano n
      -6 micro \mu (greek lower case m)
      -3 milli m
      -2 centi c
      -1 deci d
      1 deca D
      2 hecto h
      3 kilo k
      6 mega M
      9 giga G
      12 tera T
      15 peta P
      18 exa E
      21 zetta Z
      24 yotta Y

      Handy when you are working on things of these sizes, but both extreme

      • Can't wait... (Score:1, Funny)

        by Anonymous Coward
        for PC running at 200 Yhz with 256 Zettas of memory...

  • H1.5 (Score:2, Interesting)

    by Transcendent ( 204992 )
    How the hell do you have HALF of a hydrogen nucleus? .5 protons? ...so it's being reduced to quarks for a little while now?!

  • this is really stupid (Score:2, Interesting)

    by chadamir ( 665725 )
    the definition of a molecule is "The smallest particle of a substance that retains the chemical and physical properties of the substance and is composed of two or more atoms."

    Take one water molecule and it will be H2O What comes into play when multiple particles collide has nothign to do with anything

    • What's the boiling point of one molecule of water?

      if not for the hydrogen bonds between adjacent H2O molecules, water would have a much lower boiling point than is observed. A single molecule of H2O would have no hydrogen bonding. Perhaps it's boiling point would be in line with the rest of the H2_ series (The BP of H2S is about -60C, for example). Thus, because it does not have all the physical properties, an H2O molecule is not the same as a water molecule. In fact, we don't get the behaviour of wate

  • Wish there was more detail on the experiment (Score:5, Insightful)

    by jgoemat ( 565882 ) on Monday August 04, 2003 @02:26AM (#6603974)
    This does not mean that water molecules have one and a half hydrogen atoms at all. If you use electrolysis to separate the hydrogen and oxygen from a quantity of water, you will get VERY close to twice the number of oxygen atoms as hydrogen. If they gave a little more detail on their experiments it would be helpful to judge what they actually mean.

    For instance, if they are just shooting electrons and neutrons at water and counting how many hit hydrogen nuclei and how many hit oxygen nuclei, you would expect a larger number than normal to hit oxygen since the nucleus is larger (three times the protons and neutrons of hydrogen). They do say "25% fewer protons than expected", but they don't say what they expected or why.

    Also, did they have the water in a vacuum chamber? If not, there would be dissolved gasses present in the water that their beam could hit as well. I didn't notice any count for Nitrogen so they must not have done it in a glass sitting on a table, but they don't say.

  • No not the article, THIS: If protons can sometimes seem invisible to electrons and neutrons, then what about also sometimes invisible to other protons? If yes, then can that "sometimes" finally explain both the positive and the negative Cold Fusion experiments?
  • "Well duh, it's H(OH)!"?
  • What if you counted the other stuff that is disolved within the water? Especially in cities with older pipes.

    We may have CH2O or FeH1.5O.

    I know those of us who went to public schools know what I'm talking about.
  • And I thought the funny taste was from the haloacetic acid.

  • Too fast? (Score:2, Insightful)

    by Mark of THE CITY ( 97325 )
    If the interaction lasts 10^-18 s, then by special relativity the neutron couldn't interact with anything more than 0.3 nanometer away, or 3 angstrom. Any chance that the experiment is too fast to see the surroundings?
  • Sesqui is the prefix for 1.5, so...
    H-Sesqu-O
    Pronounced: (three syllables) h * cess * quo '

    Of course, I don't believe them. (I have an MS in Organic Chemistry). Lets see them get out a Dissolved Oxygen Meter [horiba.com] and prove that dissolved oxygen isn't affecting their results...
  • To physical chemists this is old hat.

    What this basically means is that water exists in a networkd (read hydrogen bonded) state where hydrogen and oxygen atoms are shared, so the effective formula is a bit different.

    Won't affect the textbooks, don't worry!!

    • To physical chemists this is old hat. What this basically means is that water exists in a networkd (read hydrogen bonded) state where hydrogen and oxygen atoms are shared, so the effective formula is a bit different.

      No, the editing/summary of the paper isn't very good. The thing is, one expects to the contributions of the scattering of the individual atoms to sum linearly at the energies used. An analogy might be that you found a compound that was more or less radioactive than expected from the proportio
  • attoseconds (less than 10-15 seconds).

    Yeah, like about 10-15 seconds LESS than 10-15 seconds.

    An attosecond is 10^-18s. Your description, while perfectly accurate, could still be accurate if it were 19 orders of magnitude smaller. :)

  • Chemically speaking...

    A molecule is something with a molecular formula, made up of a specific number of atoms (i.e., integer numbers). It also has a particular shape and its bonds are arranged in a particular way. Change one atom or one bond and you change the molecule and its properties.

    A compound (like some of the zeolites and semiconductors others have mentioned) is a mix of bonded atoms that, on average have a formula that may contain fractions or decimals. Because this is an average, the compound

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