Chemistry

Problem

A hypothetical redox process occurs under standard conditions according to the unbalanced equation

A(s) + B^{2+}(aq) \to A^{2+}(aq) + B(s)

The standard molar Gibbs free-energy change for the reaction written with the smallest whole-number coefficients is $ \Delta G^\circ = -150\,\text{kJ}$. Faraday’s constant:

F = 9.65 \times 10^{4}\,\text{C mol}^{-1}

. a. Part 1: (a) Without performing a detailed numerical calculation, state the algebraic sign (positive, negative, or zero) of the standard cell potential for the reaction as written and justify your answer in terms of thermodynamic favorability. b. Part 2: (b) Imagine the reaction were instead written with every stoichiometric coefficient multiplied by two. Predict the new numerical value of

\Delta G^\circ

and describe qualitatively how, if at all, the standard cell potential would change. Provide reasoning. c. Part 3: (c) A different redox reaction has the same standard cell potential you identified in part (a) but involves transfer of twice as many electrons per mole of reaction. Compare the magnitude of

\Delta G^\circ

for this new reaction with

-150\,\text{kJ}

and justify your prediction.

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