Chapter 14, Problem 53QP

Balance the following half-reactions, adding ${\text{OH}}^{-}\left(aq\right),{\text{H}}_2\text{O}\left(l\right),$ and electrons as appropriate.

$\begin{array}{l}\left(\text{a}\right)\text{ La}\left(s\right)\to \text{La}{\left(\text{OH}\right)}_{\text{3}}\left(s\right)\hfill \\ \left(\text{b}\right){\text{ NO}}_3^{-}\left(aq\right)\to {\text{NO}}_2^{-}\left(aq\right)\hfill \\ \left(\text{c}\right){\text{ H}}_{\text{2}}{\text{O}}_{\text{2}}\left(aq\right)\to {\text{O}}_2\left(g\right)\hfill \\ \left(\text{d}\right){\text{ Cl}}_{\text{2}}{\text{O}}_{\text{7}}\left(aq\right)\to {\text{ClO}}_2^{-}\left(aq\right)\hfill \end{array}$