Chapter 16, Problem 63E

Classify each half-reaction occurring in acidic aqueous solution as an oxidation or a reduction and balance the half-reaction.

a. ${\text{MnO}}_4^{-}(aq)\to {\text{Mn}}^{\text{2+}}(aq)$

b. ${\text{Pb}}^{2+}(aq)\to {\text{PbO}}_2(s)$

c. ${\text{IO}}_3^{-}(aq)\to {\text{I}}_2(s)$

d. ${\text{SO}}_2(g)\to {\text{SO}}_4^{2-}(aq)$