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Calculate the quantity of electricity de...

Calculate the quantity of electricity dellvered by a Daniel celi initially containing 1 L each of 1M `Cu^(2+)` ion and 1M `Zn^(2+)` C which is operated until potential drops to 1V. Given `E^(@) Zn^(2+)//Zn=-0.76V, E_(Cu^(2+)//Cu)^(@)=+0.34V`

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To solve the problem of calculating the quantity of electricity delivered by a Daniel cell, we can follow these steps: ### Step 1: Calculate the standard cell potential (E°cell) The standard cell potential can be calculated using the formula: \[ E°_{cell} = E°_{cathode} - E°_{anode} \] Given: - \( E°_{Cu^{2+}/Cu} = +0.34V \) (cathode) - \( E°_{Zn^{2+}/Zn} = -0.76V \) (anode) Substituting the values: \[ E°_{cell} = 0.34V - (-0.76V) \] \[ E°_{cell} = 0.34V + 0.76V \] \[ E°_{cell} = 1.10V \] ### Step 2: Write the half-reactions At the anode (oxidation): \[ Zn \rightarrow Zn^{2+} + 2e^- \] At the cathode (reduction): \[ Cu^{2+} + 2e^- \rightarrow Cu \] ### Step 3: Write the overall cell reaction Combining the half-reactions gives us: \[ Zn + Cu^{2+} \rightarrow Zn^{2+} + Cu \] ### Step 4: Use the Nernst equation to find the conditions when Ecell = 1V The Nernst equation is given by: \[ E_{cell} = E°_{cell} - \frac{0.059}{n} \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) \] Where: - \( n = 2 \) (number of electrons transferred) Setting \( E_{cell} = 1V \): \[ 1V = 1.10V - \frac{0.059}{2} \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) \] Rearranging gives: \[ \frac{0.059}{2} \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) = 1.10V - 1V \] \[ \frac{0.059}{2} \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) = 0.10V \] Now, multiplying both sides by \( \frac{2}{0.059} \): \[ \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) = \frac{0.10 \times 2}{0.059} \] \[ \log \left( \frac{[Zn^{2+}]}{[Cu^{2+}]} \right) \approx 3.3898 \] ### Step 5: Solve for concentrations This implies: \[ \frac{[Zn^{2+}]}{[Cu^{2+}]} = 10^{3.3898} \] Calculating this gives: \[ [Zn^{2+}] \approx 2451.2 \times [Cu^{2+}] \] ### Step 6: Determine the change in concentration Let \( x \) be the amount of \( Zn \) oxidized and \( Cu^{2+} \) reduced: - Initial concentrations: \( [Zn^{2+}] = 0 \) and \( [Cu^{2+}] = 1 \) - After reaction: \( [Zn^{2+}] = x \) and \( [Cu^{2+}] = 1 - x \) From the ratio: \[ x = 2451.2(1 - x) \] Solving this gives: \[ x + 2451.2x = 2451.2 \] \[ 2452.2x = 2451.2 \] \[ x \approx 0.9996 \] ### Step 7: Calculate the quantity of electricity The quantity of electricity (Q) can be calculated using: \[ Q = n \times F \times moles \] Where: - \( n = 2 \) (from the balanced equation) - \( F = 96500 \, C/mol \) - Moles of \( Zn \) oxidized = \( 0.9996 \, mol \) Thus: \[ Q = 2 \times 96500 \times 0.9996 \] \[ Q \approx 192249.2 \, C \] ### Final Answer The quantity of electricity delivered by the Daniel cell is approximately **192249.2 Coulombs**. ---
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