Rosemary Ainslie COP>17 Circuit / A First Application on a Hot Water Cylinder

[Rosemary Ainslie]

Rosemary, I guess this is at the basis of your misunderstanding:

On the contrary. It is exactly the formation of the ions due to the negative value of the change in Gibbs free energy of the chemical reaction leading to the formation of these ions that is the very cause for the follow-up directed flow of electrons along the solid conductors connecting the anode and the cathode.

LOL Omnibus - you were too quick.  I modified my post within 10 minutes of posting to address this very point and you posted your reply about an hour after that.  Check it out.  I changed the wording from 'cause' to the 'material of'.  So indeed you are right and indeed I know this.   

Also, as I said before, it is not true that:

They in fact can. There's no theoretical reason preventing them from flowing in concert and that can very easily be demonstrated experimentally. Electrons can and do share a path, despite being of the same charge, as do the like-charged cations on the one hand and the anions on the other in an electrolytic cell.

The little electrolysis that I understand is courtesy the explanations offered by Farrah.  And unless I'm doing her teaching a gross injustice - I understand that the cation and anion separation is into atomic and/or molecular structures that 'divide' the burden of charge equally into localised areas of the cell mix - wherever that locality is required.  Therefore, in a lead/acid battery example, one gets the lead surfaces sulphated, for instance as the liquid itself turns into pure water.   After all - the negative current flow - during the recharge of the battery - does not result in a redistribution of those sulphates.  It actually just recongregates the previous sulphuric mix.  So.  There is no proof of electron current flow here - only of 'charged' current flow.  I'm still being obtuse.  What I'm trying to point to is that the number of electrons in that mix is 'fixed' and relates to the cation and anion state of the atoms and molecules.  No surplus is ever evident.  For your concept of current flow to be valid would REQUIRE the introduction of a stream of electrons - thereby representing a surplus to the mix - which would then move through that cell - somehow - to come out the other side.  When there is ever experimental evidence of this then, indeed, I will be happy to be convinced. 

Many of us here are quite open minded, some even to the extreme, but there are limits especially when the question concerns well established experimental facts.

  Omnibut - far be it from me to disturb the thinking of you chemists.  The fact is that those of you who are 'open minded' are asking us who also 'open minded' to buy into two mutually exclusive definitions of current flow as per WIKI when both rely on the flow of electrons.  Electrons would unequivocally first need to defy the Laws of Charge to shape themselves into a field - and they would need to be remarkably versatile to introduce both a positive and a negative property into any element in a circuit to manage all that you assume.  The electrons in an atom are indeed a measure of the atomic charge which is reflected in the condition of those valence electrons.  The fact is that Pauli's exclusion principle relies on the fact that particles obey the laws of charge.  His conclusion being that no two elctrons can share the same path in an atom.  This observation was the genius insight that resulted in the systematic unfolding of the atom.  Particles unequivocally obey the Laws of Charge.  Why do you all suppose that - under circumstances of current flow - they suddenly get a mind of their own and then move in a way that it entirely impossible under all circumstances?  Those Laws of Charge - they're not a 'rule' - they're a LAW. 

This argument is not an eccentric philosophy as you here imply.  It is a deeply held conviction on the part of all theoretical purists.  The problem is that there is nothing 'known' or 'accepted' to substitute the concept of a flow of electrons.  Hopefully when this is uncovered then the broad 'misconception' of electron current flow can be put right.


Kindest regards,
Rosemary

[Rosemary Ainslie]

Omnibus - if my argument is still not clear - let me try this.  Let us say that for the electrolytic process in a battery to be initiated it first requires the accumulation of electrons at one terminal of the battery.  This way one can keep to the concept of a 'fixed number' of electrons.  So.  They charge through the circuit from one terminal to the other.  Then a switching process comes into play and the current flow is reversed.  Then those same electrons charge through the wire in the opposite direction and do what?  Do they then undo what they previously did?  Do they restructure the electrolytic mix back to its original state?  And if so, then how do they do this?  Surely - under such circumstances they would simply continue their work and sulphate more of the lead while they neutralised more of the liquid?  They presumably are still negatively charged?  They cannot now introduce a positive charge.  They're negative particles.  How do they now undo what you have assumed that they first did. 

One can then get obscurely technical and say that when they accumulate at one or other surface of the terminal then the other is postively charged by comparision.  But that would first require that all are either at one or other terminal.  The entire concept of current flow is that it is a continuous stream through that circuit material.  If electrons are streaming through and as electrons are negatively charged then both terminals would need to be negatively charged.  I can see it argued that eventually the charge distribution may be more apparent as the plates become sulphated.  But that positive and negative condition is actually only apparent through our voltmeters when the process is initiated.  At it's conclusion the voltmeter shows little if any voltage imbalance.

Or presumably one can say that charge is determined by the direction of movement - which is correct.  But that would attribute a variable charge to an electron - assuming first that it indeed can flow in a path.  Because, what is also known is that current flow can vary it's directional flow depending on voltage potential.  It seems to possess the properties of both a negative and positive charge.  Electrons do not have this advantage.  The only thing that is known to be bipolar is a magnetic field and that's it.  All else is charged or neutral.   

Again, with utmost repect to your own thinking.  I must admit you're in very good company.  I've said it often.  Purists may argue electron current flow  - but never very loudly.  There are no accepted alternative concepts - as yet.

Best regards,
Rosemary

[Omnibus]

Rsemary,

For your concept of current flow to be valid would REQUIRE the introduction of a stream of electrons - thereby representing a surplus to the mix - which would then move through that cell - somehow - to come out the other side.  When there is ever experimental evidence of this then, indeed, I will be happy to be convinced.

In fact, this is exactly what happens in an electrolytic cell. There is surplus of electrons and that surplus is contained in the electrode which has the tendency to produce the electrons. There are ample sources in the net explaining how this happens. For instance, in a Cu-Zn galvanic cell the Zn electrode is the supplier of the electrons due to the reaction Zn - 2e -> Zn2+ The Zn electrode will be the source of these electeons flowing through the wire shorting the anode and cathode until its (of the Zn) complete diappearance. So, yes, there is a surplus of electrons in an electrolytic cell if you want to call this way the supply of the electrons and that's the very essence of what an electrolytic cell is. That surplus of electrons is contained in the Zn piece and it only waits to be connected in a proper system so that is can be delivered. The delivery will continue until the full disappearance of the Zn piece.

Once you understand the above which is an experimental fact also, there will be no need to imagine that electrons cannot chare the same path because they, as experiment shows, actually do. Let alone that the Pauli exclusion principle, the basis of a speculation they don't, does not pertain to electrons that aren't bound as is the case at hand. Not to say that the electrons in a galvanic cell do obey the law of charge because all the generated electrons originating from the Zn electrode in our example do end up converting the equivalent amount of Cu2+ ions at the cathode into Cu. All of them. Charge balance is obeyed in full and it is indeed eccentric to deny it.

[Rosemary Ainslie]

Rsemary,

In fact, this is exactly what happens in an electrolytic cell. There is surplus of electrons and that surplus is contained in the electrode which has the tendency to produce the electrons.

Omnibus.  From WHERE does the electrode produce electrons? This 'tendancy' as you put it...how do you explain this?  Are you talking about the electrons within the anode itself? Those electrons that belong to the material of the anode or the cathode?  Or are you talking about electrons that have been moved there as a function of the electrolytic process from within the electrolytic mix of the cell?

If the former then there are no 'free electrons' in that material.  They only belong to the atoms and molecules of either the anode or the cathode.  No free electrons there that I know you're all looking for.  If the latter - then those electrons belonging to the cell go nowhere other than in the reconstitution of the electrolytic mix.  So far there are NO extra electrons.

There are ample sources in the net explaining how this happens. For instance, in a Cu-Zn galvanic cell the Zn electrode is the supplier of the electrons due to the reaction Zn - 2e -> Zn2+ The Zn electrode will be the source of these electrons flowing through the wire shorting the anode and cathode until its (of the Zn) complete diappearance.

I'm well aware that the zinc will be oxidised as a direct transfer of its electron to the copper.  But that says nothing about current flow.  It only explains the electrolytic process.  But current can be generated without any chemical process.  It can be generated from a motor where there is NO EVIDENCE of change in the material either of circuit components nor the material of the motor generating that current.  NO galvanic - voltaic involvement - anywhere.  Where then do those 'electrons' come from if electric current flow is the flow of electrons?  And in the simple copper/zinc example that you gave - you show NO extra electrons.  The zinc sheds its electron - the copper gains it.  Both occur within the battery cell through the salt bridge.  How does that constitute electron current flow?  Now.  Reverse the current flow through that battery.  What happens now?  Do those electrons suddenly become positive that they reverse that process so that the copper then loses its electron back to the zinc?

On the question of recharging a battery.  We KNOW that the battery can be recharged.  We KNOW that this can be done by hooking the battery to a utility supply source.  The assumption you reference is that the supply source is delivering electrons - God alone knows where they would come from. But - if so, if there's this unknown source of 'free floating' electrons - then we also KNOW that the supply source has a battery hooked up in series that current MUST be routed through that recharging battery.  NOW. How does it go from anode back to the cathode?  Through the battery?  That's NEVER been experimentally evident - never been verified.

So, yes, there is a surplus of electrons in an electrolytic cell if you want to call this way the supply of the electrons and that's the very essence of what an electrolytic cell is. That surplus of electrons is contained in the Zn piece and it only waits to be connected in a proper system so that is can be delivered. The delivery will continue until the full disappearance of the Zn piece. 

I am NOT arguing extra electrons.  My advise is that there are NO FREE FLOATING ELECTRONS.  If there were we would be very aware of them. 

Once you understand the above which is an experimental fact

If any of your claims were experimentally verifiable I would not have an argument.  I have spent many years trying to find evidence of this 'electron' current flow.  It is neither logically nor experimentally evident.  Yes they can be transferred from one atom to another, from one molecule to another.  But they CANNOT become a field.  The CANNOT flow as current.

also, there will be no need to imagine that electrons cannot chare the same path because they, as experiment shows, actually do.

Where do they share the same path?  Are you talking about the fact that there's a consistency in their drift as they reconstitute in a mix?  That is NOT an electric current path.  That is a chemical or an electrolytic process. 

Let alone that the Pauli exclusion principle, the basis of a speculation they don't, does not pertain to electrons that aren't bound as is the case at hand. Not to say that the electrons in a galvanic cell do obey the law of charge because all the generated electrons originating from the Zn electrode in our example do end up converting the equivalent amount of Cu2+ ions at the cathode into Cu. All of them. Charge balance is obeyed in full and it is indeed eccentric to deny it.

I agree.  Finally.  Charge balance is obeyed in full as it's based on the laws of charge.  But you are not arguing electron current flow here.  It would indeed be eccentric to deny the validity of chemical experiments that can prove the reconstitution of a mix from an acid or alkaline base to a neutral condition of charge.  What I'm arguing here is that current flow has NOTHING to do with the flow of electrons - free floating or otherwise.  They simply CANNOT share a path.

Regards,
Rosemary

[Omnibus]

Rosemary, I don't know what that mix you're referring to is. The turning of Zn into Zn2+ and 2e-, however, is undeniable. That's the first thing you have to understand. Second, it is undeniable that the thus produced electrons share the same path along the solid conductor connecting the Zn with the Cu. This can be measured, it is demonstrable.

The mentioned flow of e- along the common path is driven by a potential difference. It is immaterial how you create this potential difference as long as the electrons sense it forcing them to share the undeniable, experimentally observable, common path. It can be due, as I said, to the natural chemical tendency, expressed by the negative change of the Gibbs free energy (a natural property) or it can be due to some other source of energy (say, spending energy when turning the crank of a dynamo). In any event, electrons are available and one only needs to spend energy in order to force them along an observable common path. Simple as that.