The reduction potential of hydrogen half cell will be negative if :

Options

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

Answer

C

Explanation

`2H^(+)+2e^(-) to H_2`
`therefore RP=0.0-(0.059)/2 "log" (P_(H_2))/([H^+]^2)`