Dissociation of the Water Molecule

[Farrah Day]

Loner, short and sweet as per usual  nice to have you back.

Agreed, you don't have to understand how something is happening at molecular level to have a working unit.  My point was merely that if you do have an idea of what is actually occuring at molecular level then you should be able to tailor a design to more efficiently achieve the desired results. What I do rebel against is when people invent their own explanation for things that they have absolutely no real knowledge of - or that has no foundation in real science - and then claim it as science fact.

Newbie

Don't get me wrong about the Kanzius phenomenon, I'm not 100% convinced by it, but I've got to say that I'm more inclined to believe than not!  Agreed there is nothing in the way of independent proof that I know of, but after considering all the available info I'm leaning toward it more probably being fact than fiction. I'm fully aware that my opinion is not based on any qualifying science... and so has yet to be substantiated, but it ultimately comes down to, dare I say it, my 'gut feeling'! 

And 13.8 mhz is way under the energy required to ionize water with photons (really about 1e15 Hz)

Don't be too sure about this, remember that water self-ionises without any external influences.  Furthermore, it will be the influence of the RF on the Na+ and Cl- inducing movement that causes the water to ionise, not directly the EM radiation.

I'm currently constructing something that may provide me with a little more info on this phenomenon.

d3 said:

there is a lot missing from your understanding of electrolysis.

No kidding... if you have anything useful to proffer, then please, by all means enlighten me!

[newbie123]

Ok, here is something to think about. 

If we have, for convenience, let's say distilled water to which we add sodium sulphate as an electrolyte, we then have clusters of H2O molecules intermingled with sodium ions (Na+) and Sulphate ions (SO4-).

We place in the solution two inert electrodes and apply a voltage to those electrodes. Ion current flows and we get hydrogen evolving from the cathode and oxygen evolving from the anode. The sodium and sulphate ions take no part in the final reaction, so remain in the solution. So, why do not all the +ve sodium ions concregate on the surface of the cathode and halt the process?  Why do not all the -ve sulphate ions congregate on the anode and halt the process?

The devil is often in the detail, and it's little details like this that niggle away at me. No one has ever been able to provide me with an answer to this seemingly simple question - and I've others too!

Here is how I imagine it..  an electrolyte solution can be thought of as  a "hydrogen bond network"    here is a good image:  http://gold.cchem.berkeley.edu/Pictures_and_Images/H2O.jpg      ..You can probably imagine how Na+ and SO- fit into the picture.

The H3O+ and OH- ions are said to "flicker" back and forth between ions and H2O...    Near the anode and the cathode, the "ion" density will be higher .. i.e.   They flicker back and forth more often, or stay "on" longer  than the in the middle of the cell...  But since they "flicker" .....  electrons will always be able to pass through...    The electrons pass through "ion chains" just similar to how  hydrogen atoms "propagate" through an electrolyte using the Grotthus mechanism..   Note:   ions do not "Flow" through the electrolyte normally.

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

[Farrah Day]

Hi Newbie

See how quickly simple electrolysis becomes 'not quite so simple' and somewhat open to interpretation.

Near the anode and the cathode, the "ion" density will be higher .. i.e.   They flicker back and forth more often, or stay "on" longer  than the in the middle of the cell...  But since they "flicker" .....  electrons will always be able to pass through...    The electrons pass through "ion chains" just similar to how  hydrogen atoms "propagate" through an electrolyte using the Grotthus mechanism..   Note:   ions do not "Flow" through the electrolyte normally.

I'm not sure why the ion density would be higher near the electrodes than in the middle of the cell as the current thorough the cell will be uniform throughout.  I've heard said before that ionisation only takes place at or near the electrodes, but, right or wrong, I do not agree with this. The point is that only at the electrodes can charges be exchanged to evolve the gases - water ionising too far from the electrodes will simply recombine before it gets to the electrodes, and hence we have an inherent inefficiency of standard electrolysis. 

So I personally think that the ion density will remain constant throughout the liquid, but we only see results of ionisation near or at the electrodes because that's where the crucial reaction takes place. Neither do I personally think the ions of water remain as ions for any longer near the electrodes than those further from the electrodes... why would they?  Exactly the same gradient of potential exhibits itself on the ions at any given place in the solution between the electrodes.

As ions are the current carriers in liquids, I'm not sure what you mean by' "The electrons pass through 'ion chains' just similar to how hydrogen atoms (ions) propagate through a liquid'.

To the best of my knowledge electrons are not the current carriers in liquids and are only lost from anions when they reach a source of +ve 'holes'.

The hydrogen ion uses the Grotthus Mechanism because a single proton is so unstable that it cannot exist on it's own for long so will combine with the nearest available molecule, but the much larger hydroxyl ion travels through the liquid more 'normally'.

So, given that after a time you would expect the anode to be polarised by SO4- ions, how do the OH- ions so easily get through this barrier of like charges to the electrode? 

Furthermore, why is it that there never comes a point at which current flow ceases because all the sodium ions are pulled to the cathode and all of the sulphate ions are pulled to the anode?

[newbie123]

Don't be too sure about this, remember that water self-ionises without any external influences.  Furthermore, it will be the influence of the RF on the Na+ and Cl- inducing movement that causes the water to ionise, not directly the EM radiation.

True..
Self-ionization is an interesting concept..

Electric field fluctuations (electrons bouncing around...  via zero-point energy?)  in water will cause two H2O molecules to "bounce" into each other with enough energy to self-ionize and become H3O+ and OH- ... Then back to H2O ("flicker")   Which requires .828 eV per interaction at 25C...   This happens once every 10 hours per water molecule (pair).

How much energy is "exchanged" though this mechanism?  Here's my best guess..

There are 1000 grams in one liter of water, and 18.01528 grams/mole in liquid water.     

(1000 grams) / (18.01528 g/mol) =  55.5 mol

So,  one liter has 55.5 moles, or 3.34e25 water molecules.      (55.5 mol)  *  (avogadro's number)

Each (pair) of H2O molecules (2H2O)  is said  to  self-ionize once every (10 hours) or once every  36,000 seconds... 

Or you can say  (1 / 36,000) water molecules are 'self-ionizing' every  second...


So out of     3.34e25    water molecules (one liter)  ... There are (1 / 36000)  * 3.34e25   = 9.27e20    self ionizations ocuring every second

Which should required  (.828 eV) * (9.27e20) = 123 Joules / Second   or  123  Watt-Hours per liter..   Is this right? this seems a lot higher than I imagined..     I probably made a mistake or two.

[newbie123]

Hi Newbie

See how quickly simple electrolysis becomes 'not quite so simple' and somewhat open to interpretation.

I'm not sure why the ion density would be higher near the electrodes than in the middle of the cell as the current thorough the cell will be uniform throughout.  I've heard said before that ionisation only takes place at or near the electrodes, but, right or wrong, I do not agree with this. The point is that only at the electrodes can charges be exchanged to evolve the gases - water ionising too far from the electrodes will simply recombine before it gets to the electrodes, and hence we have an inherent inefficiency of standard electrolysis. 

So I personally think that the ion density will remain constant throughout the liquid, but we only see results of ionisation near or at the electrodes because that's where the crucial reaction takes place. Neither do I personally think the ions of water remain as ions for any longer near the electrodes than those further from the electrodes... why would they?  Exactly the same gradient of potential exhibits itself on the ions at any given place in the solution between the electrodes.

Here is an example for you.   When you perform electrolysis in a cell  for a while... Then turn off the cell..     You'll have a voltage potential difference between electrodes ... Where does this voltage come from?            The voltage isn't there because the ions are equally distributed throughout the cell.   

As ions are the current carriers in liquids, I'm not sure what you mean by' "The electrons pass through 'ion chains' just similar to how hydrogen atoms (ions) propagate through a liquid'.

Well, would   electrons would be able to  pass through a (hypethetical)  solution of pure OH- , or even pure H3O+ ?     I don't believe so...  I'll try to find a good reference.