aeacfm
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voltage, electron donor &electron accepetor
my friend told me some thing i looked for it but i didnt find useful thing, he said that :
electron donor has more electrons so if you measure the voltage by pH electrode it will give you -ve potential , electron accepetors are electron
dificient so using ph electrode it will give the +ve potential
i did that i measured the mv for acids it give +ve , for bases it gives -ve !!! so is that right or just accident or it will depend ?
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1281371269
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This doesn't make sense - voltage isn't a measure of the number of electrons, but rather their flow. +ve and -ve relate to the direction of flow, not
to the amount of electrons available
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aeacfm
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so no relation between donor , dificient and voltage sign
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squirrelwax
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it would depend on were you attached the other electrode.
in a sense you would need to have some were for the electrons to flow too or in the opposite case
some were to come from.
yes splitting of the moon I like that way of looking at it.
makes me wonder if a lot of this is written in code so it is not abused by us not so holy peoples.
truly all this code I think is killing more people than it was intended too.
Even the matrix has a sence of humour ;P
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TheOrbit
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| Quote: |
yes splitting of the moon I like that way of looking at it.
makes me wonder if a lot of this is written in code so it is not abused by us not so holy peoples.
truly all this code I think is killing more people than it was intended too. |
what is meaning of all this talk, he asked a question and need an answer 
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squirrelwax
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answer given 
it would depend on were you attached the other electrode.
in a sense you would need to have some were for the electrons to flow too or in the opposite case
some were to come from.
it is quite common for some one to comment on somebodies signiture here my fiery friend
and yes it would depend on were you attached the negative electrode or in case you got them swaped around
the possitive electrode.
both electrodes on the possitive of a battery does not make a current now does it.
place possitive in solution and then earth the negative and you shall get an answer.
edit:
still with a ph probe both to my knowlage are in a bubble
with a liquid to change current flow.
so in one sense one of the electrodes is touching the liquid
in the flask were as the other is touching a liquid or salt that
is cycling the current back to the solution.
this membrain has a set resistance. so you get a difference
in voltage depending on the amount of electrons available
in the solution.
acids will travel one direction ie negative volts bases the other
ie possitve volts.
still its just a volt meter so a multimeter with the negative earthed will tell you this.
I found the idea of splitting the moon to be very interesting indeed as I have not heard of the notion.
though I think I have an idea of what it is meant to mean.
and I dont think that its in wiki either if you wish to dig up some sort of ref.
but for things like ph it is always on the nail in wiki so
here she is
https://secure.wikimedia.org/wikipedia/en/wiki/PH_meter
http://ar.wikipedia.org/wiki/%D9%85%D9%82%D9%8A%D8%A7%D8%B3_...
still it is something that is going to make me read more about religon something I turned from a long long
time ago.
sorry if I insulted and was too vague.
mad as a hatter till the end hehe.
[Edited on 23-1-2011 by squirrelwax]
[Edited on 23-1-2011 by squirrelwax]
Even the matrix has a sence of humour ;P
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aeacfm
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Quote: Originally posted by squirrelwax  | it would yes splitting of the moon I like that way of looking at it.
makes me wonder if a lot of this is written in code so it is not abused by us not so holy peoples.
truly all this code I think is killing more people than it was intended too.
|
- you like it - good news
but that code you talking about is in the mind of people who can see the truth and never follow it
about people you wonder about killing them "really i dont understand exactly what you are talking about ??????
any way thanks for you respectable reply
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peach
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Technically, voltage is a measurement of the charge difference between two given points; the field gradient. Current is a measure of the charge flow
past a given point.***
I think your friend may have been talking about redox potential, which is measured in millivolts. It is also called ORP (Oxidative Reductive Potential).
I can swap the display on my pH meter to show redox values;
The unit after the number is now mV
------------------------------------------------------------------------------
***
You can of coarse have a voltage without any current, as in static electricity and capacitors
You can also have a current without any voltage. Superconductors require exactly 0 voltage across them to sustain a current. They are
an example of a perfect measurement, a very rare thing! And, lacking any static resistance, they can theoretically keep a current flowing in a ring
for an infinite amount of time without any voltage present. The properties of superconductors, I can describe them in no other way than odd! There is
more going on than them simply having a low resistance in the normal understanding of conduction. Electrons appear to be pairing and travelling as
wave functions through the lattice, as opposed to particles. The quantum probability of the wave function remaining stable DOES set a time limit on
how long the conductor can support a current without a voltage, but it's something on the scale of billions of years. There is also inductive loss to
consider.
Their ability to maintain currents for so long is another reason why people want to understand them - which we don't have a consensus on yet. They are
essentially perfect batteries. If we had a big ring of superconductor attached to our wind turbines, it could scoop up the energy and store it when
people weren't using it, then dump it back out on demand with zero loss. You can imagine how impressive that would be if the material functioned at
room temperature and the storage unit was as simple as a ring of the material.
They also display other strange properties. They don't have an unlimited current carrying capacity. When the current exceeds a certain level, magnetic
vortexes in the surface begin moving around, and the superconducting effect is lost. Superconductors are perfect magnetic shields, the field can not
penetrate the surface below a single wave length. But there is another property called the Meissner effect that demonstrates that this can't be due to their zero resistance alone.
Superconducting shields are used, along with gradiometers, in magnetoencepholographic (MEG) scanners. Which can detect the magnetic fields coming from
the ions moving through the membranes in the neurons of your brain. MEG is not MRI. The scanners are so sensitive, the building needs designing around
them.
Superconductors are also made into superconducting quantum interference detectors (SQUIDs), which are the sensors used in MEG scanners and there are
some in the gravity probe B experiment measuring the gyroscopes' spin orientation.
SQUIDs are the most sensitive magnetic field detectors possible and quantify magnetic fields into discrete units - which is all part of superstring
theory; that space is not an infinitely continuous structure, but has discrete intervals at it's fundamental level.
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White Yeti
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By definition, an electron donor is just a substance that returns to a more stable state when it loses an electron or two. This would characterise all
the alkali metals and alkali Earth metals:
Na ----> Na+ + e- +2.71V
In fact most of the transition metals that have an oxidation state of 0 will also be electron donors (copper, gold and silver being exceptions):
Zn ----> Zn+2 + 2e- +.7618V
Fe2+ + 2 e− -----> Fe(s) -.44V
In case you didn't know, you can flip the reactions backwards to change the sign of the electrode potential (the more positive it is, the more
favourable the reaction).
On the other hand, an electron acceptor is a substance that usually has an element oxidised to a very highly oxidised state and thus returns to a
stable state once it gets reduced by electrons:
[FeO4]2− + 3 e− + 8 H+ ----> Fe3+ + 4 H2O +2.20V
This is one of my personal favourites, notice how oxidised the iron atom is, (+6). Iron is stable once it's either reduced or oxidised to +3 or +2.
So as a piece of trivia, some elements can act as both electron acceptors and donors. Iron here is a perfect example, but manganese, sulphur and
chromium can also do this.
The standard electrode potentials will give you the TENDENCY or favourability for a reaction to occur. It doesn't always mean that when you put two
half cells together, you will get the exact voltage indicated in a standard electrode potential table. These voltages will give you a ball park range
of where the voltages should be IDEALLY, but the voltage of a battery can depend on many factors, quality of construction being a major one, one that
is oftentimes overlooked.
"Ja, Kalzium, das ist alles!" -Otto Loewi
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