In a galvanic cell, electrons play a crucial role in the electrochemical reactions that occur at the electrodes. Here's what happens to electrons at each electrode:
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Anode: At the anode, oxidation takes place. This means that a species (such as a metal or an ion) loses electrons. The electrons released during this oxidation process flow from the anode through the external circuit toward the cathode. The anode is considered the negative electrode in a galvanic cell, as it is the source of electrons.
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Cathode: At the cathode, reduction occurs. This involves a species gaining electrons. The electrons that flow through the external circuit arrive at the cathode, where they participate in chemical reactions that reduce an ion or compound present at the cathode. The cathode is labeled as the positive electrode in a galvanic cell because it attracts the electrons from the external circuit.
In summary, during operation:
- Electrons are produced at the anode (oxidation) and flow towards the cathode.
- Electrons are consumed at the cathode (reduction).
This flow of electrons generates an electric current that can be harnessed to do work, such as powering a device.