91Ó°ÊÓ

Use the oxidation-number method to balance the following net ionic redox equations. $$ \mathrm{Zn}+\mathrm{NO}_{3}^{-} \rightarrow \mathrm{Zn}^{2+}+\mathrm{NO}_{2} \quad \text {(in acid solution)} $$

Use the oxidation-number method to balance the following net ionic redox equations. $$ \text {Challenge} \quad \mathrm{I}-(\mathrm{aq})+\mathrm{MnO}_{4}^{-}(\mathrm{aq}) \rightarrow \mathrm{I}_{2}(\mathrm{s})+\mathrm{MnO}_{2}(\mathrm{s}) \quad \text {(in basic solution)} $$

Use the half-reaction method to balance the redox equations. Begin by writing the oxidation and reduction half-reactions. Leave the balanced equation in ionic form. $$ \mathrm{Cr}_{2} \mathrm{O}_{7}^{-}(\mathrm{aq})+\mathrm{I}^{-}(\mathrm{aq}) \rightarrow \mathrm{Cr}^{3+}(\mathrm{aq})+\mathrm{I}_{2}(\mathrm{s}) \quad \text {(in acid solution)} $$

Use the half-reaction method to balance the redox equations. Begin by writing the oxidation and reduction half-reactions. Leave the balanced equation in ionic form. $$ \mathrm{Mn}^{2+}(\mathrm{aq})+\mathrm{BiO}_{3}^{-}(\mathrm{aq}) \rightarrow \mathrm{MnO}_{4}^{-}(\mathrm{aq})+\mathrm{Bi}^{2+}(\mathrm{aq}) \quad \text {(in acid solution)} $$

Use the half-reaction method to balance the redox equations. Begin by writing the oxidation and reduction half-reactions. Leave the balanced equation in ionic form. $$ \text {Challenge} \quad \mathrm{N}_{2} \mathrm{O}(\mathrm{g})+\mathrm{ClO}^{-}(\mathrm{aq}) \rightarrow \mathrm{NO}_{2}^{-}(\mathrm{aq})+\mathrm{Cl}^{-}(\mathrm{aq}) \quad \text {(in basic solution)} $$

Explain how changes in oxidation number are related to the electrons transferred in a redox reaction. How are the changes related to the processes of oxidation and reduction?

Describe why it is important to know the conditions under which an aqueous oxidation-reducation reaction takes place in order to balance the ionic equation for the reaction.

Explain the steps of the oxidation-number method of balancing equations.

State what an oxidation half-reaction shows. What does a reduction half- reaction show?

Write the oxidation and reduction half-reactions for the redox equation. $$ \mathrm{Pb}(\mathrm{s})+\mathrm{Pd}\left(\mathrm{NO}_{3}\right)_{2}(\mathrm{aq}) \rightarrow \mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}(\mathrm{aq})+\mathrm{Pd}(\mathrm{s}) $$