Volta's Frog's Leg Experiment - Electrolysis or Thermoelectricity?

Many people appear to presume that the muscular convulsions induced in dissected frog's legs by Alessandro Volta (see http://book.boot.users.btopenworld.com/frogsleg.htm ) using dissimilar
metal rods must be caused by some form of electrolytic reaction.
However, Professor Lukyan Ivanovich Anatychuk, Director of the Institute of Thermoelectricity at the National Academy of Sciences in the Ukraine and perhaps the world's leading authority on thermoelectric phenomena, believes that the convulsions are in fact caused by the thermoelectric action of the metals, and not by electrolysis.
The two scientific papers that Professor Anatychuk has published on this subject can be read at the following web link:
http://book.boot.users.btopenworld.com/Anatychuk_papers.html
And further discussion can be found in the International Thermoelectric Society's public forum pages at:
http://www.its.org/ztforum
For an elementary description of the thermoelectric effect you can go to:
http://book.boot.users.btopenworld.com/thermo2.htm
The general principle of this effect is that if two (or more) dissimilar metals are placed in contact with each other and the points of contact are maintained at different temperatures then an electrical current will flow through the metals, and the current will continue to flow for as long as the temperature difference is maintained.
There is no electrolysis involved.
Best regards,
Keith P Walsh
PS, Professor Anatychuk is a very very experienced specialist in the field of thermoelectrics. It's likely therefore that he understands thermoelectric phenomena much much better than we do.
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wrote:

I'm glad to hear that professor Anatychuk is very very experienced in thermoelectrics. Unfortunately he seems to be lacking in experience in the frog department! Hint. Frogs are cold blooded animals. Their legs are at room temperature just like the rods used to create electrolysis. That is especially true when they are dead!
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It was the fillings in their teeth what done it.
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Peter Bowditch aa #2243
The Millenium Project http://www.ratbags.com/rsoles
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| Many people appear to presume that the muscular convulsions induced in | dissected frog's legs by Alessandro Volta (see | http://book.boot.users.btopenworld.com/frogsleg.htm ) using dissimilar | metal rods must be caused by some form of electrolytic reaction. | | However, Professor Lukyan Ivanovich Anatychuk, Director of the | Institute of Thermoelectricity at the National Academy of Sciences in | the Ukraine and perhaps the world's leading authority on | thermoelectric phenomena, believes that the convulsions are in fact | caused by the thermoelectric action of the metals, and not by | electrolysis. | | The two scientific papers that Professor Anatychuk has published on | this subject can be read at the following web link: | | http://book.boot.users.btopenworld.com/Anatychuk_papers.html | | And further discussion can be found in the International | Thermoelectric Society's public forum pages at: | | http://www.its.org/ztforum | | For an elementary description of the thermoelectric effect you can go | to: | | http://book.boot.users.btopenworld.com/thermo2.htm | | The general principle of this effect is that if two (or more) | dissimilar metals are placed in contact with each other and the points | of contact are maintained at different temperatures then an electrical | current will flow through the metals, and the current will continue to | flow for as long as the temperature difference is maintained. | | There is no electrolysis involved. | | Best regards, | | Keith P Walsh | | PS, Professor Anatychuk is a very very experienced specialist in the | field of thermoelectrics. It's likely therefore that he understands | thermoelectric phenomena much much better than we do.
Many years ago Volta's experiment was repeated, by me (and a few other students), on a cricket's leg, it being more acceptable for those with delicate sensibilities to damage an insect rather than an amphibian. I know thermoelectrics much much much much much much better than you do. If you want to talk about a thermocouple then call it a thermo- couple, <http://tinyurl.com/368h9xu but don't come bouncing in here with your 'we know' trying to impress everyone with your hero's expertise. 'We' are not you. To make the muscle twitch, inject a small voltage with ANY two metals. To make a voltaic cell... but those are so commonplace you can take it up with the Energizer Bunny.
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Did you know that students in dental schools are taught to believe that dissimilar metals in contact with each other are ONLY able to produce an electric current if they become involved in an electrolytic reaction? See:
http://book.boot.users.btopenworld.com/brown.htm
(I know, nobody ever said that dentists had to be intelligent.)
And did you further know that dentists sometimes screw metal alloy retaining pins into the root sockets of patients' teeth and encase the heads of the pins in metal amalgams. (Actually dental amalgam is an inhomogeneous mixture of dissimilar metals in its own right - but that's another matter!)
There are no muscles to twitch in the upper and lower mandibles, but the teeth are very well innervated, and there are some really sensitive organs close by, especially near to the rear molars where people who eat the wrong foods and neglect their teeth can end up with some pretty large multi-metallic restorations.
Of course there may not be any connection, but I get the impression that a significant proportion of those people who suffer from chronic tinnitus (ringing in the ears) don't actually believe that their condition was caused by listening to loud rock music.
However, I always wonder if they have any - what was it that you called them?, thermocouples? yes - thermocouples in their teeth!
And teeth are subjected to temperature gradients all the time aren't they?
Best regards,
Keith P Walsh
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wrote: | | > To make the muscle twitch, inject a small voltage with ANY two metals. | | Did you know that students in dental schools are taught to believe | that dissimilar metals in contact with each other are ONLY able to | produce an electric current if they become involved in an electrolytic | reaction? See: | | http://book.boot.users.btopenworld.com/brown.htm | | (I know, nobody ever said that dentists had to be intelligent.) | | And did you further know that dentists sometimes screw metal alloy | retaining pins into the root sockets of patients' teeth and encase the | heads of the pins in metal amalgams. (Actually dental amalgam is an | inhomogeneous mixture of dissimilar metals in its own right - but | that's another matter!) | | There are no muscles to twitch in the upper and lower mandibles, but | the teeth are very well innervated, and there are some really | sensitive organs close by, especially near to the rear molars where | people who eat the wrong foods and neglect their teeth can end up with | some pretty large multi-metallic restorations. | | Of course there may not be any connection, but I get the impression | that a significant proportion of those people who suffer from chronic | tinnitus (ringing in the ears) don't actually believe that their | condition was caused by listening to loud rock music. | | However, I always wonder if they have any - what was it that you | called them?, thermocouples? yes - thermocouples in their teeth! | | And teeth are subjected to temperature gradients all the time aren't | they? | | Best regards, | | Keith P Walsh
Sodium is a volatile metal. Sodium chloride is salt. When dissolved in water the sodium and chlorine ions separate. Put salt on your steel car to make it rust faster, you are mixing two dissimilar metals in the presence of a highly reactive gas dissolved in rainwater. People that neglect their cars can end up with some pretty large multi-metallic restorations.
Thermocouples are commonly used when there is a huge temperature difference (and a glass thermometer would melt), not a small difference. Even then the current is miniscule (around 1 milliamp) and nearly always amplified. There is no comparison to the 100 amps one gets from a 12V car battery or even the tiny 100 milliamps battery in your portable MP3 player.
If you have enough temperature difference to cause pain to your teeth you are either chewing ice cubes, in a dentist's chair having them ground down, or dead in a crematorium where a thermocouple might be used. Friction causes heat. Irrigate more to remove heat, not to rinse out tooth dust.
The damage to cars (and teeth) is electrolytic (i.e. chemical), and NOT thermoelectric.
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You're avoiding the argument here.
The fact that tooth decay occurs by chemical processes has no bearing whatsoever on whether the thermoelectric potentials generated by metal dental fillings are large enough to dissipate electrical energy through the nerves in people's heads.
The findings of Professor Anatychuk's papers imply that the thermocouple effect, acting at ordinary temperature differentials, is large enough to excite neurological tissue.
(As a matter of fact if you read carefully he actually appears to imply that the thermoelectric effect acting in a single bar of homogeneous metal is sufficient to do this.)
And there is no electrolysis involved.
You haven't read those papers yet have you?
Keith P Walsh
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wrote: | > | > The damage to cars (and teeth) is electrolytic (i.e. chemical), and NOT | > thermoelectric. | | You're avoiding the argument here.
To be quite honest I'm not really interested in the argument here. The damage to cars (and teeth) is NOT thermoelectric, car temperatures remain in the normal climate range and teeth remain at blood temperature for a lifetime. Whatever your stupid argument is, the environmental conditions do not exist no matter what your crank professor thinks. Wake up to reality. Over and out.
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Crank Professor?
If you go to the website of The SAO/NASA Astrophysics Data System at:
http://www.adsabs.harvard.edu /
- and search on the name Anatychuk, you'll find a total of 21 registered scientific papers spanning a period of 43 years and citing Professor Anatychuk as author or co-author.
One paper published in 2010 and citing Anatychuk as the sole author is entitled "The Law of Thermoelectric Induction and Extending the Capabilities of Its Application".
Like I said at the start, Professor Anatychuk understands this stuff much much better than we do (much much much better, actually).
And that includes you.
(Blimey! It didn't take long to blow you out of the water did it? You sci.physics gobshites are getting easier.)
Keith P Walsh
PS, the Oxford Dictionary website at:
http://www.oxfordadvancedlearnersdictionary.com/dictionary/gobshite
defines the word "gobshite" as: "a stupid person who talks nonsense"
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wrote: | | > conditions do not exist no matter what your crank professor thinks. | | | Crank Professor?
I said "Over and out". Take the hint and FUCK OFF, cretin!
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Does that mean you're not going to read those papers?
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wrote: | | > I said "Over and out". | > Take the hint and FUCK OFF, cretin! | | | Does that mean you're not going to read those papers? |
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*plonk*

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You've never managed to explain to me how the mercury and silver in amalgams are "maintained at different temperatures". If they aren't, then where does this electrical current you talk about come from?
--
Peter Bowditch aa #2243
The Millenium Project http://www.ratbags.com/rsoles
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That's because he, like you, is a babbling kook.
A $17 multimeter from Radio Shack is more than enough test equipment to determine the voltage source.
--
Jim Pennino

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According to my memory and also the link you report below, it was Luigi Galvani the first to do such experiments.

"Towards the end of the eighteenth century, Luigi Galvani, Professor of Anatomy at Bologna University in Italy, published a book describing a series of investigations he had made on the subject of "animal electricity"".

Sorry for the OT.
Regards, Angelo
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Thank you for your contribution.
Yes, Galvani was the first to do the frog's leg experiments.
But unfortunately for him he received the late-eighteenth-century version of being sent to "alt.fuckwits" for suggesting that the explanation for the effect was "animal electricity". (Galvani later re- established his reputation with good work in electrolytic cells.)
Volta was one of the scientists who didn't believe Galvani's explanation, and he repeated the experiments for himself to demonstrate that, as my reference suggests, "the two dissimilar metals were more important than the leg".
It appears that Volta also experimented with the influence of temperature difference on the observed effects, and it is Professor Anatychuk's review of this work which has led him to suggest in his published papers that Volta was the first person to record experimental evidence of the thermoelectric effect; some 15 to 20 years before Seebeck, who is usually credited with its discovery.
Have you read Professor Anatychuk's papers yet?
Best regards,
Keith P Walsh
PS, What's "the OT"?
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wrote:

There are two experiments in question here. First were Galvani's experiments. However, the really famous experiment was Volt's experiment. Reading your link, it is apparent that Volta really was talking about an electrolytic affect. His fellow countryman, Alessandro Volta, could not agree with this but believed that the two dissimilar metals were more important than the leg. Subsequently, Volta did some experiments to show that electricity was produced when two different metals were separated by various non-animal liquids and these practically settled the matter in his favour. In Voltas experiments, the metals were separated by some non- animal liquid. Sure sounds like electrolytic current to me. A thermoelectric effect wouldnt need a liquid to separate the two metals. The original experiments by Galvanni may have involved the Seebeck effect. Galvanni showed the two wires connected at a single junction. Each metal touched a different part of the frogs leg. Galvanni didnt mention a liquid. Again, I dont think thermoelectricity had anything to do with it. The Seebeck effect requires a large temperature difference between the two different wires. http://en.wikipedia.org/wiki/Thermoelectric_effect The Seebeck effect is the conversion of temperature differences directly into electricity. The Seebeck effect is commonly used in a device called a thermocouple (because it is made from a coupling or junction of materials, usually metals) to measure a temperature difference directly or to measure an absolute temperature by setting one end to a known temperature. A metal of unknown composition can be classified by its thermoelectric effect if a metallic probe of known composition, kept at a constant temperature, is held in contact with it. Industrial quality control instruments use this Seebeck effect to identify metal alloys. This is known as thermoelectric alloy sorting. Several thermocouples connected in series are called a thermopile, which is sometimes constructed in order to increase the output voltage since the voltage induced over each individual couple is small. See, the difference in one junction is very small. Galvanni used only one junction. I suspect that the current in Galvannis experiment was electrolytic, though of a different nature. A dead frog is about as cold-blooded as any animal can get. However, the body fluids of the frog were probably acidic due to bacterial action. If you touch two dissimilar materials in an acidic environment, one gets an electric current. The blood in the leg acted as a salt bridge. With all due respect to your Professor, the thermoelectric effect is usually far weaker than the electrolytic effect. You need a large temperature difference to generate a sizable electric current.
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wrote:

There are two experiments in question here. First were Galvani's experiments. However, the really famous experiment was Volt's experiment. Reading your link, it is apparent that Volta really was talking about an electrolytic affect. His fellow countryman, Alessandro Volta, could not agree with this but believed that the two dissimilar metals were more important than the leg. Subsequently, Volta did some experiments to show that electricity was produced when two different metals were separated by various non-animal liquids and these practically settled the matter in his favour. In Voltas experiments, the metals were separated by some non- animal liquid. Sure sounds like electrolytic current to me. A thermoelectric effect wouldnt need a liquid to separate the two metals. The original experiments by Galvanni may have involved the Seebeck effect. Galvanni showed the two wires connected at a single junction. Each metal touched a different part of the frogs leg. Galvanni didnt mention a liquid. Again, I dont think
=========================================We already know that, drosean.
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wrote:

Two dissimilar metals placed in contact with each can generate an electric current if the two metals are at different temperatures. This is how the common thermocouple works. However, metals are not very efficient thermoelectric materials because they conduct electricity. There are other materials that generate electric currents. However, most of them are semiconductors or insulators. In order to generate significant voltage, the material must have a high resistance to electric current. Otherwise, the smallest difference in electric potential causes a large electric current. In order to make the frogs legs twitch, the electric potential must be large enough to send electric current through the frogs leg. Maybe the thermoelectric voltage was large enough. However, I would have to ask two questions: 1) What was the source of the difference in temperature between the two metals? 2) How what was the resistance of the two metals? I think electrolytic reactions are far more likely to cause sufficient voltage. As I originally heard the story, Volta had a series of plates in an acidic solution. I don't remember any mention of the plates being heated. That doesn't mean you are wrong. I would just like to hear more.
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1) What was the source of the difference in temperature between the two metals? =====================================There is no difference in temperature between the two metals, doofus, they run side-by-side! The thermocouple has a difference in temperature between the two JUNCTIONS. ------------------------------ iron o-/ \ - o \___________________/ copper
Hot Cold
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