|MadSci Network: Chemistry|
I'm getting confused about this part. Many of my references say the potato contains phoshoric acid which causes the chemical rections to occur at each of the electrodes. The copper electrode electrons and acid form hydrogen gas,then the phoshoric acid desolve the Zinc giving positive IONs from the electons that stay on the electrode. These Zn++ migrate in the electrolytic solution Acid Juices in the potato then if the Zinc and copper electrodes are connected a electric current flows. But, I read your achived message ID# 943757681.Ch and ID#916286185.PH, these say it's not the Acid in the potato, and state the Salts in the potato are the source of the ions, (Sodium +, and Chlorine -). In those references the Na+ and Cl- are what charge the electrodes and the elctrons are the carriers for the electricity. Can you please help me reconcile this information?
Let's take this one thing at a time.
To sum up: any ions can carry the charges through the potato. Acid makes the battery work better because it provides a place for the copper electrode to dump electrons. You could get the same voltage with just salt water, but probably not as much current. The reason that hydrogen gas doesn't build up in commercial flashlight batteries (though you can get a hydrogen explosion if you work very hard at force-charging a car battery) is that they are designed to have other sorts of electron dumps than acid.
Incidentally, the reason you don't get much current from these beasties is that the transfer of electrons from zinc to copper is not very efficient. To get a higher-current battery you need something that's hungrier for electrons than a weak acid.
I hope this is helpful. Thanks for giving us the opportunity to clarify our answer!
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