Calculate the potential of hydrogen electrode in contact with a soluti

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

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

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