For an electrochemical cell with standard potential E_cell^0 = +1.10 V at 298 K, what is the sign and meaning of standard Gibbs free energy change Delta G^0?
Answer and explanation
Correct answer: B. Delta G^0 is negative
- Step 1: Thermodynamic relation: Delta G^0 = -n F E_cell^0, where n and Faraday constant F are positive. Step 2. Since E_cell^0 > 0, Delta G^0 is negative (-212 kJ/mol for n = 2), indicating standard spontaneity. Answer: Delta G^0 is negative. Why not the others: Positive cell potential always corresponds to negative Gibbs free energy change.
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