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Calculate Delta G^(Theta) and E(cell) fo...

Calculate `Delta G^(Theta)` and `E_(cell)` for the cell `Al |Al^(3+) (0.01 M) || Fe^(2+) (0.02 M) |Fe`
Given that `E_((Al^(3+)|Al))^(Theta) = -1.66 V` and `E_((Fe^(2+) |Fe))^(Theta) = -0.44 V`

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To solve the problem, we need to calculate the standard Gibbs free energy change (ΔG°) and the cell potential (E_cell) for the given electrochemical cell: **Cell Notation:** Al | Al³⁺ (0.01 M) || Fe²⁺ (0.02 M) | Fe **Given Data:** - Standard reduction potential for Al³⁺/Al: E°(Al³⁺/Al) = -1.66 V - Standard reduction potential for Fe²⁺/Fe: E°(Fe²⁺/Fe) = -0.44 V ### Step 1: Identify the half-reactions 1. **Anode (oxidation)**: - Aluminum is oxidized: \[ \text{Al} \rightarrow \text{Al}^{3+} + 3e^- \] The standard oxidation potential (E°) for this reaction is the negative of the reduction potential: \[ E°_{\text{oxidation}} = +1.66 \, V \] 2. **Cathode (reduction)**: - Iron is reduced: \[ \text{Fe}^{2+} + 2e^- \rightarrow \text{Fe} \] The standard reduction potential is given: \[ E°_{\text{reduction}} = -0.44 \, V \] ### Step 2: Balance the half-reactions To balance the electrons transferred, we need to multiply the half-reactions so that the number of electrons is the same. - Multiply the aluminum oxidation half-reaction by 2: \[ 2 \text{Al} \rightarrow 2 \text{Al}^{3+} + 6e^- \] - Multiply the iron reduction half-reaction by 3: \[ 3 \text{Fe}^{2+} + 6e^- \rightarrow 3 \text{Fe} \] ### Step 3: Write the overall balanced reaction Combining the balanced half-reactions gives: \[ 2 \text{Al} + 3 \text{Fe}^{2+} \rightarrow 2 \text{Al}^{3+} + 3 \text{Fe} \] ### Step 4: Calculate the standard cell potential (E°_cell) Using the formula: \[ E°_{\text{cell}} = E°_{\text{cathode}} - E°_{\text{anode}} \] Substituting the values: \[ E°_{\text{cell}} = (-0.44 \, V) - (-1.66 \, V) = 1.22 \, V \] ### Step 5: Calculate the cell potential under non-standard conditions using the Nernst equation The Nernst equation is given by: \[ E_{\text{cell}} = E°_{\text{cell}} - \frac{0.0591}{n} \log \left( \frac{[\text{products}]}{[\text{reactants}]} \right) \] Where: - n = number of moles of electrons transferred = 6 (from the balanced equation) - Concentrations: [Al³⁺] = 0.01 M, [Fe²⁺] = 0.02 M Substituting into the Nernst equation: \[ E_{\text{cell}} = 1.22 - \frac{0.0591}{6} \log \left( \frac{(0.01)^2}{(0.02)^3} \right) \] Calculating the logarithm: \[ \log \left( \frac{(0.01)^2}{(0.02)^3} \right) = \log \left( \frac{0.0001}{0.000008} \right) = \log(12.5) \approx 1.096 \] Now substituting back: \[ E_{\text{cell}} = 1.22 - \frac{0.0591}{6} \times 1.096 \] \[ E_{\text{cell}} = 1.22 - 0.0091 \approx 1.209 \, V \] ### Step 6: Calculate ΔG° Using the formula: \[ \Delta G° = -nFE°_{\text{cell}} \] Where: - F (Faraday's constant) = 96485 C/mol Substituting the values: \[ \Delta G° = -6 \times 96485 \times 1.22 \] \[ \Delta G° = -706380 \, J \approx -706.38 \, kJ \] ### Final Answers: - \( E_{\text{cell}} \approx 1.209 \, V \) - \( \Delta G° \approx -706.38 \, kJ \)

To solve the problem, we need to calculate the standard Gibbs free energy change (ΔG°) and the cell potential (E_cell) for the given electrochemical cell: **Cell Notation:** Al | Al³⁺ (0.01 M) || Fe²⁺ (0.02 M) | Fe **Given Data:** - Standard reduction potential for Al³⁺/Al: E°(Al³⁺/Al) = -1.66 V - Standard reduction potential for Fe²⁺/Fe: E°(Fe²⁺/Fe) = -0.44 V ...
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