Fe3+ + 1e- -> Fe2+

E = E° - 0,059*Log[Fe++]/[Fe+++] = 0.771 - 0.059*Log(0.145 / 2*0.145) = 0.789 V

2H+ + 2e- -> H2(g)

E = E° - 0.059/2*Log(PH2 / [H+]^2) = 0 - 0.059/2*Log( 1 / X^2) = + 0.059/2 * LogX^2 = + 0.059 * LogX

fem = 1 = 0,789 - 0.059*LogX

LogX = (1 - 0.789) / (- 0.059) = -3,58

X = 10^-3.58 = 2,63*10^-4 = [H+]

[H2SO4] = 2.63*10^-4 / 2 = 1.31*10^-4 M