Calculate the potential of hydrogen electrode in contact with a solution whose `pH=10`.

Explanation

If pH of solutions is 10 then its `[H^(+)]` ion concentration will be `10^(-10)M`. Let us consider a reduction half cell `H^(+)(10^(-10)M)|H_(2)(1 "atm")|Pt`
Electrode process :
`2H^(+)(10^(-10)M)+2e^(-)hArrH_(2)(1"atm")(n=2)`
`Q=(PH_(2))/([H^(+)]^(2))=(1)/([10^(-10)])=10^(20)`
According to to Nernst equation
`E_(H^(+)//H_(2))=E_(H^(+)//H_(2))^(0)-(0.059)/(n)"log Q"`
`=0-(0.059)/(2)"log10"^(20)=-0.59V`