Under standard conditions, a spontaneous electrochemical cell always has which combination of thermodynamic signs?
Answer and explanation
Correct answer: B. ΔG° < 0 and E°_cell > 0
- Step 1: Relate Gibbs free energy to cell potential: .
- Step 2: For a spontaneous process under standard conditions, must be negative (). This directly requires standard cell potential to be positive ().
Answer
ΔG° < 0 and E°_cell > 0.
Why not the others: indicates a non-spontaneous process; negative cell potential indicates electrolytic behavior; zero values indicate dynamic equilibrium.
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