Chapter 17, Problem 3E

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

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

(b) $\text{Cr}\to {\text{Cr}}^{3+}+3{\text{e}}^{-}$

(c) ${\text{MnO}}_4{}^{2-}\to {\text{MnO}}_4{}^{-}+{\text{e}}^{-}$

(d) ${\text{Li}}^{+}+{\text{e}}^{-}\to \text{Li}$