Chapter 17, Problem 4E

For each of the following balanced half-reactions, determine whether an oxidation or reduction is occurring.

(a) ${\text{Cl}}^{-}+3{\text{e}}^{-}\to {\text{Cl}}_2$

(b) ${\text{Mn}}^{2+}\to {\text{MnO}}_2$

(c) ${\text{H}}_2\to {\text{H}}^{+}$

(d) ${\text{NO}}_3{}^{-}\to \text{NO}$