Chemistry

Problem

\text{NO}_3^- \rightarrow \text{NO}_2

(acidic medium);

E^\circ = 0.790\ \text{V}

and

\text{NO}_3^- \rightarrow \text{NH}_2\text{OH}

(acidic medium);

E^\circ = 0.731\ \text{V}

. At what pH will the above two half-reactions have the same

E

values? Assume the concentrations of all the species are unity.