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At 298K the standard free energy of form...

At 298K the standard free energy of formation of `H_(2)O(l)` is `-256.5 kJ..mol`, while that of its ionisation to `H^(+)` & `OH^(-)` is `80 kJ//mol`. What will be emf at 298 K of the cell.
`H_(2)(g,1 bar) |H^(+)(1M) || O_(2)(g,1bar)`
Fill your answer by multiplying it with 10.

Text Solution

Verified by Experts

The correct Answer is:
`005`
`H_(2) +H_(2)O +(1)/(2)O_(2) rarr 2H^(+) +2OH^(-)`
`DeltaG^(@) =- 256.5 +2 xx 80 = -96.5 kJ`
`-DeltaG^(@) = nFE^(@)`
`+96.5 xx 1000 = 2 xx 96500 xx E^(@)`
`E^(@) = 0.5` volt
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