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Author Topic: How does table salt affect a voltaic pile?  (Read 7982 times)

Offline sorin cezar

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How does table salt affect a voltaic pile?
« on: 22/10/2013 10:40:21 »
Some experiments able to bring a new interpretation for Volta battery are performed. To be more precise, the experiments put in light the unusual effect of kitchen salt added to the electrolyte (water) and the huge impact of this action over the magnitude of generated electric current.
A strip of Zn and a strip of Cu are immersed into deionized water and the voltage and current between these electrodes are measured. In our experiments the surface of Cu and Zn strips is about 3 cm2 and when about 1 cm2 of each of them is immersed into water the current in circuit is about 12 microA; a potential difference of 0,72V can be detected by a voltmeter. Both electrodes are fixed with some mechanical devices in order to have a constant surface of contact between these homemade electrodes and water.
Then, keeping the ammeter on, a small spoon of kitchen salt is thrown into water. Quite immediately, the current into circuit boost to 1,05 mA.
If supplementary the water is agitated using a common magnetic agitator, the current into circuit further increases to 4 mA.

How can be interpreted this experiment?
NaCl does not react either with water, or Zn or Cu.
We have accepted for few hundreds years that a chemical reaction can generate an electric current if electrons are forced to move in an external circuit. Here no new reaction takes place ..but the current is increasing…with a factor of one thousand...
How can NaCl generate electrons in the external circuit?????
« Last Edit: 01/11/2013 22:26:05 by chris »


 

Offline alancalverd

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Re: The kitchen salt effect and Volta battery
« Reply #1 on: 22/10/2013 14:36:54 »
It doesn't. See my reply to your previous posting.

The electrolyte is irrelevant to the voltage of a primary cell but the greater the ionic condictivity of the electrolyte, the more current you can extract from it. If you move the plates closer together, you will get more current too because you have reduced the impedance of the electroyte. Agitation removes any reaction products or trapped gas from the surface of the electrodes and thus increases the surface area in contact and reduces the surface impedance.
 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #2 on: 22/10/2013 19:42:29 »
"How can NaCl generate electrons in the external circuit?????"
It doesn't.
It just makes it easier for them to get through the electrolyte.
 

Offline SimpleEngineer

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Re: The kitchen salt effect and Volta battery
« Reply #3 on: 23/10/2013 13:56:50 »

NaCl does not react either with water, or Zn or Cu.


Sigh.. it does.. please research your 'facts' before stating them.

The addition of NaCl to water causes the following reaction

NaCl             <---> Na+ + Cl-
H2O             <---> H+ + OH-
H+ + CL-     <---> HCl
OH- + Na+  <---> NaOH

lots and lots of lovely ionic reactions (totally reversible in normal conditions)

Lots of lovely ions around allowing for greater conductivity
 

Offline chiralSPO

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Re: The kitchen salt effect and Volta battery
« Reply #4 on: 23/10/2013 14:49:44 »
Deionized water is a terrible conductor of current (for the purpose of my response current = net movement of charge per time). Dissolving ions in the water allows for current. If negative ions flow to one plate, and positive ions flow to the other, the associated currents are additive. An ionic solution completes a circuit, but not by the movement of "free" electrons as could be described for a wire. Instead it is just the movement of the ions.

We actually measure the resistivity of water to determine its purity: 18 megaOhm*cm is a standard rating for deionized water.
« Last Edit: 23/10/2013 14:55:56 by chiralSPO »
 

Offline sorin cezar

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Re: The kitchen salt effect and Volta battery
« Reply #5 on: 24/10/2013 15:44:37 »
Again ... people you are missing the point....

In chemistry when I add a ionic compound to a solution the speed of other concurent reaction must decrease because the increase of  ionic strength diminish the speed of main reaction.
In our case, an electric current cannot be amplified by a ionization of NaCl....
The current is generated by the reaction of Zn with water (there is any other reaction when I add NaCl).
Increasing the conductibility of solution doeas not push the electrons faster from  Zn toward the other electrod of Cu.
If electrons travells through electrolite as bored chemist says in this case I have internal shortcircuit and the current in external circuit have to drop to zero....

But the new post with a cell having a covalent compound as a salt bridge ... would open a new horizon for you ...
 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #6 on: 24/10/2013 19:38:04 »
Explaining what happens is not "missing the point".

"Increasing the conductibility of solution doeas not push the electrons faster from  Zn toward the other electrod of Cu. "
Nobody said it did.
However the extra ions in the solutuion make it much easier for charge to get round the circuit


"But the new post with a cell having a covalent compound as a salt bridge ... would open a new horizon for you"
It might, but you haven't done that, on another page somewhere you connect two cells in series which is nothing special is it?
 

Offline sorin cezar

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Re: The kitchen salt effect and Volta battery
« Reply #7 on: 26/10/2013 09:56:48 »
Adding the extra ions in solution lower the reaction between Zn and water ... and if the speed of reaction is diminished, there are not so many electrons to travell ... so the electric current has to diminish.
An electric current is generated by a chemical reaction taking place in the system.
 IF NO REACTION... NO CURRENT
IF DIMINISHED SPEED REACTION THEN DIMINISHED INTENSITY CURRENT
This is the point.

For those who do not want to see.....there will be nothing new in the world...
 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #8 on: 26/10/2013 16:39:16 »
You have not understood what is controlling the rate of the reaction here.
Just for a start, think about this "Adding the extra ions in solution lower the reaction between Zn and water "
Do you think the same "logic" would apply to the reaction between iron and water?
There's no great difference- they are both electro-positive metals.
OK, do you know that things go rusty faster in sea water than in fresh water?
OK so now you know that this "Adding the extra ions in solution lower the reaction between Zn and water " is just wrong.

So why not take the trouble to think about things before posting nonsense (like this ""Adding the extra ions in solution lower the reaction between Zn and water") and then following it up with "For those who do not want to see.....there will be nothing new in the world..."?
 

Offline sorin cezar

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Re: The kitchen salt effect and Volta battery
« Reply #9 on: 28/10/2013 14:38:45 »
I pointed out that NaCl added to water has no chance to increase the speed of the existent chemical reaction.
The fact that electrolite is more ionic, does not increase the curent ,,per se". So there is no explanation for the ,,kitchen salt effect".
 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #10 on: 28/10/2013 19:54:51 »
"I pointed out that NaCl added to water has no chance to increase the speed of the existent chemical reaction. "
You did say that, but it isn't true. It's like the case of iron rusting faster in salt water.
So why did you say it again?

"The fact that electrolite is more ionic, does not increase the curent ,,per se". So there is no explanation for the ,,kitchen salt effect"."

There is an explanation.
Alan, Chiral and I have all pointed it out to you.
It's just that you won't listen, or don't understand it.
 

Offline sorin cezar

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Re: The kitchen salt effect and Volta battery
« Reply #11 on: 29/10/2013 10:03:26 »
Ok ... I missed the explanation or the ideea as you say ....
I do not see any ,,physical or chemical effect" able to increase the electric current ...
But if you say so .... the new experiment with a simple battery and  few grams of sodium chloride, by sure will bring a little bit light ...



 

Offline SimpleEngineer

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Re: The kitchen salt effect and Volta battery
« Reply #12 on: 29/10/2013 14:02:52 »
A reduction in resistance would increase the current maybe?..
 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #13 on: 29/10/2013 19:25:25 »
Thanks Simpleengineer.
Now that 4 people have pointed it out, perhaps Sorin will see it.

Just in case he still hasn't.
Here are the points again.
From Alan
"greater the ionic condictivity of the electrolyte, the more current you can extract from it. "
From me
"It just makes it easier for them to get through the electrolyte."
From Chiral
"Dissolving ions in the water allows for current. "
From me again
"However the extra ions in the solution make it much easier for charge to get round the circuit"
And
"You have not understood what is controlling the rate of the reaction here."
And, from SimpleEngineer
"A reduction in resistance would increase the current maybe?.."

Sorin,
Do you see a theme here?

 

Offline sorin cezar

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Re: The kitchen salt effect and Volta battery
« Reply #14 on: 31/10/2013 11:01:18 »
It seems you don t want to stick to the facts and you stick to the opinions.

I agree that  one can extract more current into a sollution, because the greater the conductivity, the more current will flow into it. This means you have an independent source and you power it through a solution ....
This is not the case here... because the current must flow in external circuit.
In case the conductivity is greater you have internal shortcircuit.
Why should an electric current pass through a external resistance, and do a mecanic work, when there is the possibility to flow through a smaller resistance path.
Chemistry and physics works with ,,facts" and not with oppinions. I cannot detail more here, not because I do not know .. but I prepare a new material with a new ,,fundamental effect in science" and after a week we can come back to the topic, if you will want ..



 

 

Offline Bored chemist

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Re: The kitchen salt effect and Volta battery
« Reply #15 on: 31/10/2013 19:02:45 »
I cannot detail more here, not because I do not know .

Indeed, so I suggest you learn a lot before yo come back with more misunderstandings.
 

Offline sorin cezar

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Re: How does table salt affect a voltaic pile?
« Reply #16 on: 05/11/2013 10:21:39 »
There is a new post with a new effect in science,I supposed it was moved in the new experiments category...
You can see there that a electric current can be generated in absence of a chemical reaction or a magnetic field...
This is what I underlined... not the fact I do not understand what is happen in solution ...
 

Offline alancalverd

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Re: How does table salt affect a voltaic pile?
« Reply #17 on: 05/11/2013 10:46:05 »
The current is generated by the reaction of Zn with water

And there is the underlying mistake. The Zn-H2O reaction is irrelevant. The driving voltage is due to the difference in electronegativity V between Zn and Cu. The current I = V/R where R is the resistance of the electrolyte, which decreases as you add more ions. 
 

Offline Bored chemist

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Re: How does table salt affect a voltaic pile?
« Reply #18 on: 05/11/2013 20:58:17 »
"There is a new post with a new effect in science"
I'm willing to bet my house against a  stick of chewing gum that that statement is incorrect.
 

Offline sorin cezar

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Re: How does table salt affect a voltaic pile?
« Reply #19 on: 03/12/2013 08:29:08 »
Bet accepted...
Give me the address of a estate agency where you put the documents of your house and the contract and I will come there...
As far you want to bet for a chewing gum there is no need to prove I have a chewing gum ...
 

Offline Bored chemist

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Re: How does table salt affect a voltaic pile?
« Reply #20 on: 03/12/2013 19:41:33 »
Bet accepted...
Give me the address of a estate agency where you put the documents of your house and the contract and I will come there...
As far you want to bet for a chewing gum there is no need to prove I have a chewing gum ...

You would need to win first.
Where is the "new science?"
Do you have any evidence, or should I just ask you to post me the gum?
« Last Edit: 03/12/2013 19:54:40 by Bored chemist »
 

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Re: How does table salt affect a voltaic pile?
« Reply #20 on: 03/12/2013 19:41:33 »

 

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