noob --
Resonant frequency is the wrong way to think about it. Acoustic wavelengths are far too large to ever do anything at the molecular level--the energy density just isn't there. Cavitation is a good acoustic energy focuser, but probably no more efficient than electrolysis.
I'll point you here--
http://www.scs.uiuc.edu/suslick/britannica.html
-Brian
Resonant frequency is the wrong way to think about it. Acoustic wavelengths are far too large to ever do anything at the molecular level--the energy density just isn't there. Cavitation is a good acoustic energy focuser, but probably no more efficient than electrolysis.
I'll point you here--
http://www.scs.uiuc.edu/suslick/britannica.html
-Brian
I've been thinking of ways to replicate Meyer's experiment with electrolysis and I've recently come across Hydrogen MASERs. They don't appear to be commercially available and I don't know a whole lot about them. It seems however that they deal with oscillating distribution of high-range frequencies to measure resonance at an atomic level (used in atomic clocks). I was looking at the long metal tubes that meyer was using in his prototype and thinking that they resembled Organ-tubes like the ones you see in cathedrals and such. Perhaps the shape of these tubes is the key to generating resonance and the circular shape of the enclosing case serves to retain that resonance thus making the device more efficient in fracturing water into hydrogen and oxygen. Also, I'm curious about the properties of a hydrogen-powered internal combustion engine in comparison to a petrol-powered internal combustion engine.
Audiophilenoob said:this is a very strange question...
but I'm interested in what the resonant frequency of water is...
also I'm trying to figure out a way to generate (whatever this frequency is) at as many DB as I can underwater...
hearsay this frequency is around 42khz... but I think this is hogwash and am not willing to spend the money to try it...
I would like to see 180-190db in the water at w/e frequency this is.... and have about 10,000 watts RMS to work with in achieving it
this is a serious question BTW...
Well the others have said much good things already, I don't know if this will help any more, but anyway...
In classical acoustics, a medium (such as water) does not have a resonant frequency. Instead, resonance is determined by the dimensions of the boundaries, such as the length of an organ pipe. If there are no boundaries, there is no resonance.
One will have to go to molecular acoustics in order to find resonance in the media itself. I am not terribly good at these things, but I do know that these things occur at very high frequencies. We are talking gigahertz here. I think this is not the way to go for a hobbyist.
Instead, I would go for a resonator of some kind.
You would also have to read up on the references for sound pressure (dB) that are used. 180 dB under water is not the same as 180 dB in air.
ok i'll throw in my answer:
wouldn't you be more interested in how the speed of sound is higher in water?
resonant frequencies tend to depend on mass of the medium.... so the answer to your question is: how long is a piece of string?
I'd think you'd grab a sealed speaker and just let er rip.
wouldn't you be more interested in how the speed of sound is higher in water?
resonant frequencies tend to depend on mass of the medium.... so the answer to your question is: how long is a piece of string?
I'd think you'd grab a sealed speaker and just let er rip.
water-hydrogen-etc.
Palladium sucks up >700x its own weight of hydrogen..IIR... when subjected to a cathodic current during electrolysis... much more than other metals and alloys...
I did my thesis on using Pd as a dimensionally stable anode back in the early '70's...guess it's a good thing i wasn't using deuterium oxide, eh??? 
... works great as an almost pure hydrogen electrode... (which is why all the cold fusion debacle in the late '80's used the stuff)... guess I was ahead of my time...
The only real problems were the cost, the fact that the Pd swells up and becomes brittle... and the fact that under anodic conditions, palladium isn't very noble... (other than that, Ms. Lincoln, how was the play?)
I moved on to inventing a successful method to electroplate technetium instead...
John L
Palladium sucks up >700x its own weight of hydrogen..IIR... when subjected to a cathodic current during electrolysis... much more than other metals and alloys...
I did my thesis on using Pd as a dimensionally stable anode back in the early '70's...guess it's a good thing i wasn't using deuterium oxide, eh???
... works great as an almost pure hydrogen electrode... (which is why all the cold fusion debacle in the late '80's used the stuff)... guess I was ahead of my time... The only real problems were the cost, the fact that the Pd swells up and becomes brittle... and the fact that under anodic conditions, palladium isn't very noble...
(other than that, Ms. Lincoln, how was the play?)I moved on to inventing a successful method to electroplate technetium instead...
John L
SY said:
"One mole would take 96,500 coulombs"
This is a pretty big assumption. Is there a particular reason that you think that one mole of water will take exactly one mole of electrons to decompose it?
According to my recollection of first year chem and a big book full of words and numbers and stuff, free energy change for combustion of hydrogen is -228.59 J/mol, and if he's operating at the 72% figure from nowhere, that means he'll need 317.49 J/mol to un-combust it.
Calculated value for moles is 2313.3, so he needs a grand total of 734.46 kJ of energy, and given 600 seconds, that's 1224.1 Watts. Not a small amount to be sure, but definitely not out of the question either.
Elfer said:
That's not an assumption... it's a basic fact of electrochemistry.
96500 coulombs = 1 Faraday = 96500 amp-seconds
1 amp-second = ~6 x 10^18 electrons
You need at least 6 x 10^23 electrons to bind to the mole of protons (H+) to evolve 1 mole (6 x 10^23 atoms of elemental hydrogen
John L.
Salt water not distilled but worth looking at
Here is a recent article that is relavent http://www.post-gazette.com/pg/07252/815920-85.stm Not a lot of details but it is similar to the original subject of this thread.
Here is a recent article that is relavent http://www.post-gazette.com/pg/07252/815920-85.stm Not a lot of details but it is similar to the original subject of this thread.
More in Wikipedia http://en.wikipedia.org/wiki/John_Kanzius at the bottom is a link to "A Demonstration" that if followed links to You Tube videos.
SY said:
Ok, fine. Show me a tank of elemental hydrogen that anyone has ever produced, and I'll agree. Especially a tank of elemental hydrogen produced by resonance.
Either way, your assumption still wouldn't be right, since there's two moles of elemental hydrogen per mole of water. The electron flow needs to be twice as large. However, this only hold true if he's doing electrolysis in a Hoffman-type apparatus, which he isn't.
If he was using electrolysis, you're right, he would have some serious problems, and not just because of the current needed.
If he's trying to break down the water using resonance, then it's the thermodynamic analysis that matters, not the electrochemical analysis, since it's not an electrochemical reaction.
Also, no need to inform me of the term "stoichiometry," I'm a chemical engineering major.
Elfer said:
Since you seem to prefer to "pick nits"... elemental hydrogen is the product of electrolysis, and the aforementioned electrochemical methodology is indeed correct. Recombination into molecular hydrogen occurs later after the protons are electronated at the cathode and are desorbed.
Show us a tank of molecular hydrogen ever produced by this so-called energy efficient "resonance".
What's your point? You've made a questionable thermodynamic calculation w/o regards for the kinetics of the reaction, based on what is arguably a rather irreversible situation with a high activation energy. Thermodynamics alone doesn't provide much from a practical perspective.
As one example, decomposition of clay to monocrystalline silicon and high strength aluminum is thermodynamically possible, but in practice requires extraordinary efforts to overcome kinetic constraints such that simple calculations analogous to yours for H2 are pretty misleading
auplater said:
Actually, there's no elemental hydrogen involved anywhere in electrolysis as a product. The closest you'd have is a positively charged hydrogen ion in a transition state, and the rest of the time you'd have hydronium ions.
As for activation energy, yes, I'm aware of it. However, since he's trying to get a ridiculous amount of reaction done in such a small amount of time, he would easily have more than enough energy to overcome the activation barrier to the transition state.
Saying that combustion of hydrogen is "arguably a rather irreversible situation" is ridiculous, since you can build your own little Hoffman apparatus at home if you don't believe it can be done. Also, if I'm not hideously mistaken, the potential required for electrolysis of water is about 1.23 V, so claiming that the activation barrier for the reverse reaction is too high to overcome is also a bit silly.
As for your example, the separation of clay into its constituents is a fundamentally different problem, as the main driving force in that process is entropy rather than enthalpy.
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