Where do all the electrons go?

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If you connect copper wire to steel wire, how come the steel does not start becoming copper (or vice versa)? I'm looking at it this way. The electrons are moving in the copper, an they are then going to the steel. If the electrons are from copper and going to steel, would not the steel begin to turn to copper? I have never undeerstood this.
(of course this could be any type of metals that conduct electricity)
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pvs_industries@yaho_o.com wrote:

Elements are composed of atoms and atoms have more than just electrons in them. Protons and Neutrons are the other "big" parts. Also part of what makes an element what it is has to do with how the atoms are arranged (how they stick together).
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pvs_industries@yaho_o.com wrote:

Should have paid more attention during HS chemistry and physics... :)
It is the nucleus that determines the element, the electrons are sorta' peripheral and what are exchanged during chemical reactions and current flow while the nuclei are unmodified.
Essentially, in a very simplistic description it's the number of protons that determines which element it is (look at an atomic table); the number of neutrons along w/ the protons sets the isotope of the element.
--
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pvs_industries@yaho_o.com wrote: ...

In addition to the other note on makeup the nucleus being the determination of which atom is which, there is no net change in number of electrons/atom in current flow -- it's a "flow"; what goes away from any point (atom) has to be made up from somewhere else upstream. This only changes in instances such as charging a capacitor where some are at least temporarily stored leaving a net charge (which is simply a net excess or shortage of electrons in a localized area, still haven't created or lost any electrons in total only redistributed them).
And, only nuclear reactions change anything but the chemical composition; chemical reactions, electrical currents, etc., do not. They change only the manner in which atoms may be combined; the net number of nuclei of the original species are unchanged before, during and after. That why one can write chemical balance equations...
Fission/fusion are nuclear reactions and there's where the nuclei are either broken apart or smushed together with the result of more atoms (but smaller/lower atomic number) in fission or fewer (of higher atomic number) in fusion...
--
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On Sat, 18 Sep 2010 07:27:51 -0500, pvs_industries wrote:

You need to move the whole atom not just move electrons from one atom to the other. That's what electricity is.
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A. Baum wrote:

No. That mos' definitely is _not_ "what electricity is".
--
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On 9/18/2010 10:02 AM, A. Baum wrote:

Current flow in a conductor is only the movement of atoms.
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On 9/18/2010 2:04 PM, George wrote:

Correction: only the movement of *electrons*
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pvs_industries@yaho_o.com wrote:

Because whole atoms would have to move, they don't. Only the electrons pass along. No difference between a steel electron and a copper electron.
--
LSMFT

I look outside this morning and everything was in 3D!
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And then there are some physicists who would argue that the electrons are not moving any farther than the nearest adjacent atom. It is really the hole from the misplaced electron that is moving, the hole flow going from positive to negative.
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Those physicists would be wrong. A "hole" is different than an "electron", as far as conduction of electricity goes. Both carry current, but in different materials, and by different mechanisms.
An "electron" is a "free" electron, "bonding" electron, or "conduction" band electron. These electrons are "spare", in that they can easily be moved from one atom to another without adding energy to them.
A "hole" is where an electron was stripped (excited to a higher energy) from an already full valence band into the conduction band. This electron can be moved across to another atom, where it may fall into a "hole" in a full valence band in the next atom (or not). This "hole" in the full valence band is seen to be moving in the opposite direction.
Depending on the material (is the outer "shell" of electrons full or almost full?), "holes" or "electrons" are the main ("majority") carrier of electricity. In conductors, electrons are the majority carriers.
Electrons move farther that the nearest atom, but not quickly.
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wrote:

Sure, almost all electronics is analyzed using the (incorrect) positive current carrier model. The math works, so why not. Engineers also understand (or should) that this is only a useful model at the macro scale.

No, nothing has been rewritten, at least in the last fifty years. They are very different concepts. "Electrons" are the (majority) carriers of electrical current in conductors and "holes" are the carriers in insulators. Semiconductors are interesting in that the majority carrier can be either, depending on the material. They're "semi" because they don't act like either conductors or insulators, rather somewhere inbetween. Also interesting, in semiconductors, is that the minority carrier gets interesting.
<...>
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Holes vs. excess electrons is a semiconductor discussion at the molecular level and should not even be in this thread (IMHO).
Conventional current flow (which was arbitrarily chosen to go from + to - before anyone understood it) vs. electron flow is what is being discussed here. You could redefine current to be the opposite way, but there isn't really any reason to do that.
Finally, lumping electricity into the list of forces we don't understand isn't correct. I think electricity is fully understood these day. It is not one of the fundamental forces that are still being analyzed at a subatomic level to this day.
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On Sep 19, 12:25pm, snipped-for-privacy@neo.rr.com wrote:

A semiconductor is nothing more than a device to control the flow of electrons/holes. Which is the subject of this thread and therefore on topic. Which is also probably way more than the average reader cares to know.
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No, it is a class of materials, from which the devices got their name.

The thread itself is off-topic, but only the lowest form of pond-scum plays netkop.

You can kill the thread anytime.
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With new fraud proof voting machines, electrons all go to the Democrat headquarters.
--
Christopher A. Young
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Stormin Mormon wrote:

This is how superstition begins.
--
LSMFT

I look outside this morning and everything was in 3D!
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You are right, sort of. It's called electromigration and a real problem in integrated circuits. http://en.wikipedia.org/wiki/Electromigration.
Flowing electrons bump into atoms and push them along. The effect is really small, but when you have very small conductors with high current densities, it can cause ICs to fail by moving enough of the conductor to open a gap or push it into a lump that shorts to another conductor.
It's a weird world down there.
-- Doug
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This question should be answered by TRON.
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pvs_industries@yaho_o.com wrote:

All electrons are identical - it's the non-electron part of an atom that makes the atom a distinct element. The non-electron part, the nucleus, doesn't move (much).
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