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Calculate the maximum electrical work th...

Calculate the maximum electrical work that can be obtained from the following cell under the standard conditions at `25^(@)C`.
`Zn//Zn^(2+) (aq)"||"Fe^(2+)(aq)//Fe`
Given that `E_(Zn^(2+)(aq)//Zn)^(Theta)= -0.76V`
`E^(Theta)Fe^(2+) (aq)//Fe= -0.44 V and F = 96500"C mol"^(-1)`

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To solve the problem of calculating the maximum electrical work that can be obtained from the given electrochemical cell, we will follow these steps: ### Step 1: Identify the half-reactions and their standard electrode potentials. The cell is represented as: \[ \text{Zn} | \text{Zn}^{2+} (aq) || \text{Fe}^{2+} (aq) | \text{Fe} \] From the problem, we have: - For the zinc half-reaction: \[ \text{Zn} \rightarrow \text{Zn}^{2+} + 2e^- \quad (E^\circ = -0.76 \, \text{V}) \] - For the iron half-reaction: \[ \text{Fe}^{2+} + 2e^- \rightarrow \text{Fe} \quad (E^\circ = -0.44 \, \text{V}) \] ### Step 2: Determine the anode and cathode. - The anode is where oxidation occurs (Zn is oxidized). - The cathode is where reduction occurs (Fe²⁺ is reduced). ### Step 3: 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: \[ E^\circ_{\text{cell}} = (-0.44 \, \text{V}) - (-0.76 \, \text{V}) \] \[ E^\circ_{\text{cell}} = -0.44 + 0.76 = 0.32 \, \text{V} \] ### Step 4: Calculate the number of moles of electrons transferred (\(n\)). From the half-reactions, we see that 2 moles of electrons are transferred during the reaction: \[ n = 2 \] ### Step 5: Use the formula for Gibbs free energy change (\(\Delta G\)). The relationship between the maximum electrical work and Gibbs free energy is given by: \[ \Delta G = -nFE^\circ_{\text{cell}} \] Where: - \(F = 96500 \, \text{C/mol}\) (Faraday's constant) Substituting the values: \[ \Delta G = -2 \times 96500 \, \text{C/mol} \times 0.32 \, \text{V} \] \[ \Delta G = -2 \times 96500 \times 0.32 \] \[ \Delta G = -61,760 \, \text{J} \] Converting to kilojoules: \[ \Delta G = -61.76 \, \text{kJ} \] ### Conclusion: The maximum electrical work that can be obtained from the cell under standard conditions at \(25^\circ C\) is \(-61.76 \, \text{kJ}\). ---

To solve the problem of calculating the maximum electrical work that can be obtained from the given electrochemical cell, we will follow these steps: ### Step 1: Identify the half-reactions and their standard electrode potentials. The cell is represented as: \[ \text{Zn} | \text{Zn}^{2+} (aq) || \text{Fe}^{2+} (aq) | \text{Fe} \] From the problem, we have: - For the zinc half-reaction: ...
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