Estimate the minimum potential difference needed to reduce `Al_(2)O_(3)` at `500^(@)C` The gibbs energy change for the decomposition reaction `2/3Al_(2)O_(3)rarr4/3Al+O_(2)`is 960 kJ (F=96500 C `mol^(-1))`

Explanation

`(2)/(3)Al_(2)O_(3)rarr(4)/(3)Al+O_(2)`
`n=(6xx2)/(3)=4e`
`DeltaG=-nFE`
`DeltaG=960xx10^(3)J, n=4, F="96500 C mol"^(-1)`
`960xx10^(3)=-4xx96500xxE`
`=E=-2.487V`
`"Minimum potential difference needed to reduce "Al_(2)O_(3)=-2.487V`.