The reduction potential of hydrogen electrode will be negative if :

Options

A. `pH_(2) = 2 atm and [H^(+)] = 2.0 M`
B. `pH_(2) = 1 atm and [H^(+)] = 2.0 M`
C. `pH_(2) = 1 atm and [H^(+)] = 1.0 M`
D. `pH_(2 )= 2 atm and [H^(+)] = 1.0 M`

Answer

B

Explanation

`E=E_(H^(+)//H_(2))^(@)-(0.059)/(n)=0-(0.059)/(2)log(pH_(2))/(H^(+))^(2) =(0.59)/(2) log (2)/(1^(2))=-ve`