Do "holes" stay put while electrons move?

[jaredwoods]

salt water conducts with a positive charge and a negative charge moving in different directions. Is this different than a single electron moving through copper and the "hole" staying still? I see a lot of contradicting models.

 

[littlespark]

Electrons don’t move…. They just push against the next one, that pushes against the next one etc.

 

[marconi]

Energy band theory: conduction of electrons and holes - The Student Room - https://www.thestudentroom.co.uk/showthread.php?t=6802608

 

[littlespark]

thatll teach me to be a smart arse.



so electrons do move?

I guess if its a circuit... a circular path, then the initial hole will be filled by the first electron that was pushed out of its hole by the one behind

equal number of holes vs electrons... or there should never be a hole... as there is always an electron to fill it




my head hurts

 

[Avo Mk8]

To answer the original question, salt water "conducts" electricity in a completely different way to current flow in a conductor. Maybe better to think of it as 'electrolysis'.
This explains better than I can:
Salt water consists (mostly) of H20 molecules, Na+ ions and Cl- ions. When two electrodes are put in such a fluid with some potential difference the Na+ ions will be attracted by the negative electrode and will move (somewhat more) to that electrode. Likewise for the Cl- ions and the positive electrode.

When the voltage (potential difference) is large enough the Cl- ions at the positive electrode will give an electron to the electrode, and recombine to Cl2 molecules (or react with the electrode). You will be able to see and/or smell this. The situation at the negative side is more complex, but at that side the net result will be that the Na+ will help the H20 to get converted to H2 and OH-. You will see bubbles of H2 gas here.

The net effect is that NaCl and water become Cl2 gas and H2 gas. This is a chemical reaction. It is quite different from normal electron conduction.

 

[pc1966]

so electrons do move?

Yes, they do. But very slowly.

The "speed" of electricity is more or less the displacement of charge but what is very odd is in most cases the speed depends on the insulator separating the conductors!

Velocity factor - Wikipedia

en.wikipedia.org

 

[pc1966]

This is even better:

Speed of electricity - Wikipedia

en.wikipedia.org

"The drift velocity in a 2 mm diameter copper wire in 1 ampere current is approximately 8 cm per hour"

 

[marconi]

One needs to qualify which ‘speed of electricity’ is being discussed. There is more than one.

See:

What is the speed of electricity? - https://www.wtamu.edu/~cbaird/sq/mobile/2014/02/19/what-is-the-speed-of-electricity/