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According to Physical Science Section Test 6...q 15
Why does rust occur on the exposed metal surface of the cathode?
The reaction is Fe --> Fe2+ + 2e- making it an oxidation reaction...which occurs at the anode...right?
According to the answer, it says....
Recall that oxidation occurs at the anode, and upon oxidation iron will acquire a positive charge to become
cations. In a typical galvanic cell, because the anode and cathode are separated, the ions themselves cannot migrate,
and so charge is balanced by the movement of the ions in the salt bridge. In this case, however, no such separation is
performed, and so the positive Fe ions will be attracted to the cathode. Looking at Equation 2, which is the reaction
for the formation of rust, you can see that oxygen and water are required. Since the exposed areas of iron are rich in
oxygen and water, they serve as the cathodes and the unexposed areas serve as the anodes.
Why does rust occur on the exposed metal surface of the cathode?
The reaction is Fe --> Fe2+ + 2e- making it an oxidation reaction...which occurs at the anode...right?
According to the answer, it says....
Recall that oxidation occurs at the anode, and upon oxidation iron will acquire a positive charge to become
cations. In a typical galvanic cell, because the anode and cathode are separated, the ions themselves cannot migrate,
and so charge is balanced by the movement of the ions in the salt bridge. In this case, however, no such separation is
performed, and so the positive Fe ions will be attracted to the cathode. Looking at Equation 2, which is the reaction
for the formation of rust, you can see that oxygen and water are required. Since the exposed areas of iron are rich in
oxygen and water, they serve as the cathodes and the unexposed areas serve as the anodes.
