A horror story from UConn
Consider the reduction half-reaction 14H+ + Cr2O72– + 6e– _ 2Cr3+ + 7H2O where E0red = 1.33V. Students were asked to find pH for which E = 1.00 if all other concentrations are at 0.1 M. Nernst led to [H+]14 = 3.5 _10–35. One student asked why the answer book had pH = 2.46, not 17.65 = –log(2.24 _10–18). How did she get that?