Question

Use the table of standard reduction potentials (Table 11.1) to pick a reagent that is capable of each of the following oxidations (under standard conditions in acidic solutions)

a. Oxidizes$B{r}^{-}$to$B{r}_2$but does not oxidize$C{I}^{-}$to$C{I}_2$.

b. Oxidizes$Mn$to$M{n}^{2+}$but does not oxidize$Ni$to$N{i}^{2+}$.

Short answer

a. The speciesare$I{O_3}^{-},Mn{O}_2,O_2,C{r}_2{O_7}^{2-}$.

b. The species are $H_{2}O,Z{n}^{2+},C{r}^{3+},F{e}^{2+},C{d}^{2+},PbS{O}_4$.

Step-by-step solution

Explanation of oxidizing agent regarding part (a)

The substance that can easily reduce is an oxidizing agent. They are on the left side of reduction half-reactions. The substances that get easily oxidized are reducing agents. They are on the right side of the reduction half-reactions.

Reagents required for part (a)

The species that oxidizes Br^-to Br₂but does not oxidize Cl^-to Cl₂are$I{O_3}^{-},Mn{O}_2,O_2,C{r}_2{O_7}^{2-}$.

$$\begin{gathered} 2B{r}^{-}\to B{r}_2+2e^{-},E^0=-1.09V \\ 2C{I}^{-}\to C{I}_2+2e^{-},E^0=-1.36V \end{gathered}$$

Reagents required for part (b)

The species that oxidizes Mn to Mn²⁺but does not oxidize Ni to Ni²⁺are$H_{2}O,Z{n}^{2+},C{r}^{3+},F{e}^{2+},C{d}^{2+},PbS{O}_4$.

$$\begin{gathered} Mn\to M{n}^{2+}+2e^{-},E^0=1.18V \\ Ni\to N{i}^{2+}+2e^{-},E^0=0.23V \end{gathered}$$