# Question 20.9: Calculating the Free-Energy Change from Electrode Potentials...

Calculating the Free-Energy Change from Electrode Potentials

Using standard electrode potentials, calculate the standard free-energy change at $25^{\circ} \mathrm{C}$ for the reaction

$\mathrm{Zn}(s)+2 \mathrm{Ag}^{+}(a q) \longrightarrow \mathrm{Zn}^{2+}(a q)+2 \mathrm{Ag}(s)$

PROBLEM STRATEGY

Substitute into $\Delta G^{\circ}=-n F E_{\text {cell }}^{\circ}$. Use a table of standard electrode potentials to obtain $E_{\text {cell }}^{\circ}$. The cell reaction equals the sum of the half-reactions after they have been multiplied by factors so that the electrons cancel in the summation. Note that $n$ is the number of moles of electrons involved in each half-reaction.

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Question: 20.10

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Question: 20.14

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Question: 20.13

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Question: 20.12

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Question: 20.11

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Question: 20.8

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Question: 20.7

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