What is the standard cell potential (E°_cell) for the galvanic cell: Zn(s) | Zn²⁺(aq) || Cu²⁺(aq) | Cu(s), given E°(Cu²⁺/Cu) = +0.34 V and E°(Zn²⁺/Zn) = -0.76 V?
Answer and explanation
Correct answer: C. +1.10 V
- Step 1: Identify cathode (reduction) and anode (oxidation): Copper has a more positive reduction potential, so copper is the cathode and zinc is the anode.
- Step 2: Apply cell potential equation: .
Answer
+1.10 V.
Why not the others: +0.42 V subtracts the magnitudes; -0.42 V inverts signs; -1.10 V represents the non-spontaneous electrolytic reverse cell.
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