In a galvanic cell, a potential difference is generated by redox reactions. I know the general operation and I also know how, for example, the Daniel cell works. However, I can’t find anywhere which redox reactions take place in a potato when we include it in a closed circuit, provided with an anode (zinc plate) and cathode (copper plate). I need the chemical conversions at the electrodes. If possible, it would also be interesting to know which redox reactions take place in a lemon when it is included in the circuit, provided with a zinc anode and a copper cathode.
thanks in advance
Answer
Dear Koen,
The reactions that happen with a “potato battery” or a “lemon battery” are of course the same, and have nothing to do with the type of fruit or vegetable used.
The reaction that occurs is the following:
Zn + Cu2+ –> Cu + Zn2+
The reduction takes place at the cathode:
Cue2+ + 2nd– –> Cu
Oxidation takes place at the anode:
Zn –> Zn2+ + 2 e–
The copper ions come from an oxide layer of copper that is usually present when a copper plate has been exposed to the air for a while.
Answered by
Dr. Etienne Jooken
Chemistry
Old Market 13 3000 Leuven
https://www.kuleuven.be/
.