P-Chemistry Question on a Kaplan Full Length 7

[feathr]

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Question states (it's part of a passage but it's essentially a stand alone):
A piece of copper wire which is undergoing corrosion in a strongly basic solution can be classified as a👎:

A. Electrolytic cell with the cathode at the negative relative potential, and electrons flowing from cathode to anode through the metal.
B. galvanic cell with the cathode at positive relative potential, and electrons flowing from cathode to anode through the metal.
C. galvanic cell with the cathode at the positive relative potential, and Cu ions being reduced at the cathode.
D. electrolytic cell with the cathode at the positive relative potential, and electrons flowing away from the anode through the metal.

Answer is C, but my only problem is, why are Cu ions being reduced? If a piece of copper wire is under going corrosion, shouldn't the Cu be oxidizing at the anode? Even assuming at these two aren't mutually exclusive, why are Cu ions being reduced at all? That seems to negate the entire corrosion process.

 

[TieuBachHo]

Question states (it's part of a passage but it's essentially a stand alone):
A piece of copper wire which is undergoing corrosion in a strongly basic solution can be classified as a👎:

A. Electrolytic cell with the cathode at the negative relative potential, and electrons flowing from cathode to anode through the metal.
B. galvanic cell with the cathode at positive relative potential, and electrons flowing from cathode to anode through the metal.
C. galvanic cell with the cathode at the positive relative potential, and Cu ions being reduced at the cathode.
D. electrolytic cell with the cathode at the positive relative potential, and electrons flowing away from the anode through the metal.

Answer is C, but my only problem is, why are Cu ions being reduced? If a piece of copper wire is under going corrosion, shouldn't the Cu be oxidizing at the anode? Even assuming at these two aren't mutually exclusive, why are Cu ions being reduced at all? That seems to negate the entire corrosion process.

Read the last paragraph of the passage carefully "... an electric potential difference between the two points on the surface of a metal ..." due to imperfections create corrosion. Cu ions being reduced (The ions mean that it's Cu2+), therefore it must be reduced. Cu(s) gets oxidized but there are imperfections on the metal surface that creates potential differences. The corrosion process occurs simultaneously and spontaneously on the copper metal in a strongly BASIC solution.
This question just asks for your basic understanding of a redox reaction and its application. Don't think too hard.