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Calculate emf and DeltaG for the followi...

Calculate emf and `DeltaG` for the following reaction at 298 K
`Mg(s)|Mg^(2+)(0.01 M)||Ag^(+)(0.0001 M)|Ag(s)`
Given `E_((Mg^(2+)//Mg))^(@)=-2.37" V ", E_((Ag^(+)//Ag))^(@)=+0.80" V "`

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To solve the problem, we will follow these steps: ### Step 1: Identify the half-reactions and determine the anode and cathode. The given cell reaction is: \[ \text{Mg}(s) | \text{Mg}^{2+}(0.01 \, M) || \text{Ag}^{+}(0.0001 \, M) | \text{Ag}(s) \] - **Oxidation (Anode)**: \[ \text{Mg}(s) \rightarrow \text{Mg}^{2+} + 2e^- \] Standard reduction potential, \( E^\circ_{\text{Mg}^{2+}/\text{Mg}} = -2.37 \, V \) - **Reduction (Cathode)**: \[ \text{Ag}^{+} + e^- \rightarrow \text{Ag}(s) \] Standard reduction potential, \( E^\circ_{\text{Ag}^{+}/\text{Ag}} = +0.80 \, V \) ### Step 2: Calculate the standard cell potential \( E^\circ_{\text{cell}} \). Using the formula: \[ E^\circ_{\text{cell}} = E^\circ_{\text{cathode}} - E^\circ_{\text{anode}} \] Substituting the values: \[ E^\circ_{\text{cell}} = 0.80 \, V - (-2.37 \, V) = 0.80 \, V + 2.37 \, V = 3.17 \, V \] ### Step 3: Write the balanced overall cell reaction. The overall reaction can be written as: \[ \text{Mg}(s) + 2\text{Ag}^{+}(aq) \rightarrow \text{Mg}^{2+}(aq) + 2\text{Ag}(s) \] ### Step 4: Determine the number of electrons transferred \( N \). From the balanced equation, we see that 2 electrons are transferred: \[ N = 2 \] ### Step 5: Use the Nernst equation to calculate the cell potential \( E_{\text{cell}} \). The Nernst equation is given by: \[ E_{\text{cell}} = E^\circ_{\text{cell}} - \frac{0.0591}{N} \log \left( \frac{[\text{Mg}^{2+}]}{[\text{Ag}^{+}]^2} \right) \] Substituting the concentrations: - \([\text{Mg}^{2+}] = 0.01 \, M\) - \([\text{Ag}^{+}] = 0.0001 \, M\) Thus: \[ E_{\text{cell}} = 3.17 \, V - \frac{0.0591}{2} \log \left( \frac{0.01}{(0.0001)^2} \right) \] Calculating the logarithm: \[ \log \left( \frac{0.01}{(0.0001)^2} \right) = \log \left( \frac{0.01}{0.00000001} \right) = \log(10^8) = 8 \] Now substituting back: \[ E_{\text{cell}} = 3.17 \, V - \frac{0.0591}{2} \times 8 \] \[ E_{\text{cell}} = 3.17 \, V - 0.2364 \] \[ E_{\text{cell}} = 2.9336 \, V \] ### Step 6: Calculate \( \Delta G \) using the formula. The Gibbs free energy change \( \Delta G \) is given by: \[ \Delta G = -NFE_{\text{cell}} \] Where: - \( F = 96500 \, C/mol \) (Faraday's constant) Substituting the values: \[ \Delta G = -2 \times 96500 \times 2.9336 \] \[ \Delta G = -2 \times 96500 \times 2.9336 \approx -566,000 \, J/mol \] Converting to kilojoules: \[ \Delta G \approx -566 \, kJ/mol \] ### Final Answers: - **EMF (E_cell)**: \( 2.9336 \, V \) - **Delta G (ΔG)**: \( -566 \, kJ/mol \)

To solve the problem, we will follow these steps: ### Step 1: Identify the half-reactions and determine the anode and cathode. The given cell reaction is: \[ \text{Mg}(s) | \text{Mg}^{2+}(0.01 \, M) || \text{Ag}^{+}(0.0001 \, M) | \text{Ag}(s) \] - **Oxidation (Anode)**: \[ \text{Mg}(s) \rightarrow \text{Mg}^{2+} + 2e^- \] ...
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