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On the basis of information available fr...

On the basis of information available from the reaction
`(4)/(3)Al+O_(2) rarr (2)/(3)Al_(2)O_(3),DeltaG = -827kJ mol^(-1)` of `O_(2)`, the minimum emf required to carry out of the electrolysis of `Al_(2)O_(3)` is `(F=96,500 C mol^(-1))`

A

`2.14 V`

B

`4.28 V`

C

`6.42 V`

D

`8.56 V`

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The correct Answer is:
To find the minimum emf required to carry out the electrolysis of Al2O3 based on the given reaction and ΔG, we can follow these steps: ### Step 1: Understand the Reaction The reaction provided is: \[ \frac{4}{3} \text{Al} + \text{O}_2 \rightarrow \frac{2}{3} \text{Al}_2\text{O}_3 \] This indicates that aluminum (Al) reacts with oxygen (O2) to form aluminum oxide (Al2O3). ### Step 2: Identify ΔG We are given: \[ \Delta G = -827 \text{ kJ/mol} \] This value indicates that the reaction is spontaneous under standard conditions. ### Step 3: Convert ΔG to Joules Since we need ΔG in Joules for our calculations, we convert: \[ \Delta G = -827 \text{ kJ/mol} = -827 \times 10^3 \text{ J/mol} = -827000 \text{ J/mol} \] ### Step 4: Determine the Number of Electrons (n) From the reaction, we can see that aluminum (Al) is oxidized. Each Al atom loses 3 electrons. Since we have \(\frac{4}{3}\) moles of Al: \[ n = \frac{4}{3} \text{ moles of Al} \times 3 \text{ electrons/Al} = 4 \text{ moles of electrons} \] ### Step 5: Use the Relationship Between ΔG, n, F, and E The relationship is given by: \[ \Delta G = -nFE \] Where: - \(E\) is the emf (electromotive force) we want to find, - \(F\) is Faraday's constant, \(F = 96500 \text{ C/mol}\). ### Step 6: Rearrange the Equation to Solve for E Rearranging the equation gives: \[ E = -\frac{\Delta G}{nF} \] ### Step 7: Substitute the Values Substituting the known values: \[ E = -\frac{-827000 \text{ J/mol}}{4 \text{ mol} \times 96500 \text{ C/mol}} \] ### Step 8: Calculate E Calculating the value: \[ E = \frac{827000}{4 \times 96500} \] \[ E = \frac{827000}{386000} \] \[ E \approx 2.14 \text{ V} \] ### Conclusion The minimum emf required to carry out the electrolysis of Al2O3 is approximately **2.14 V**. ---

To find the minimum emf required to carry out the electrolysis of Al2O3 based on the given reaction and ΔG, we can follow these steps: ### Step 1: Understand the Reaction The reaction provided is: \[ \frac{4}{3} \text{Al} + \text{O}_2 \rightarrow \frac{2}{3} \text{Al}_2\text{O}_3 \] This indicates that aluminum (Al) reacts with oxygen (O2) to form aluminum oxide (Al2O3). ### Step 2: Identify ΔG ...
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On the bassis of the information available from the reaction 4/3 Al + O_2 rarr 2/3 Al_2 O_3 . Delta G =- 82 7 k J "mol"^(-1) of O_2 the minimum emf required to carry out an electorlysis of Al_2 O_3 is (F= 96500 C "mol"^(-1))

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