20. Calculate the reversible potential of oxygen electrode in a solution of \( pH =1 \), when the partial pressure of \( O _{2} \) is \( 10^{-2} \) atm [Assume \( E _{ O _{2} / H _{2} O }^{0}=1.23 V \), vs SHE at \( 1 atm \) and \( \left.25^{\circ} C \right] \)
1) \( 1.19 V \)
2) \( 1.71 V \)
3) \( 1.20 V \)
4) \( 1.112 V \)
