To what pH should you adjust a standard hydrogen electrode to get an electrode potential of -0.124V V ? (Assume that the partial pressure of hydrogen gas remains at 1 atm.)

Answer 1

2H^+ + 2e ==> H2
E = Eo -0.05916/n(log)pH2/(H+^2)
Plug in the numbers and solve for (H^+), then convert to pH.