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Tracking Copper After the Current Reverses 5 questions
Tracking Copper After the Current Reverses
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A simulation has two copper electrodes in a solution of copper ions. A copper ion gains two electrons to join an electrode as copper metal. A copper atom loses two electrons when it leaves as Cu2+. The display reverses the current between two steps.
| Step | Change in copper on P (mol) | Change in copper on Q (mol) |
|---|---|---|
| First | +0.006 | −0.006 |
| Second | −0.004 | +0.004 |
Question 1
Which electrode shows copper reduction in the second step?
- P only
- Q only
- Both electrodes
- Neither electrode
Question 2
Calculate the net copper change at each electrode across both steps.
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Question 3
A student says only 0.002 mol of copper ions gained electrons during the full test. Evaluate the claim using both gains.
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The model counts every electron involved in a copper reduction, regardless of the direction of current.
Question 4
Calculate the amount of electrons counted over the two steps.
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A final step transfers 0.002 mol copper from P to Q, restoring both electrodes to their starting amounts.
Question 5
Calculate the total amount of copper ions reduced over all three steps. Explain what the restored electrode amounts leave out.
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