The standard oxidation potential of `Ni//Ni^(2+)` electrode is `0.236 V`. If this is combined with a hydrogen electrode in acid solution, at what `pH` of this solution will be measured e.m.f. be zero at `25^(@)C`? Assume that `[Ni^(2+)] = 1 M` and `P_(H_(2)) = 1 atm`.

Options

A. 4
B. 1
C. 2
D. 3

Answer

A

Explanation

`E^(@)Ni^(+2)//Ni=-0.236V`
`E_(cell)^(@)=+0.236`
`0=0.236-(0.06)/(2)log.([Ni^(+2)])/([H^(+)]^(2))`