Answer: The half reaction that describes the reduction reaction is [tex]Fe^{2+}(aq.)+2e^-\rightarrow Fe(s)[/tex]
Explanation:
Oxidation reaction is defined as the reaction in which an atom looses its electrons. The oxidation number of the atom gets increased during this reaction.
[tex]X\rightarrow X^{n+}+ne^-[/tex]
Reduction reaction is defined as the reaction in which an atom gains electrons. The oxidation number of the atom gets reduced during this reaction.
[tex]X^{n+}+ne^-\rightarrow X[/tex]
For the given chemical reaction:
[tex]Mg(s)+Fe^{2+}(aq.)\rightarrow Mg^{2+}(aq.)+Fe(s)[/tex]
The half reactions follows:
Oxidation half reaction: [tex]Mg(s)\rightarrow Mg^{2+}(aq.)+2e^-[/tex]
Reduction half reaction: [tex]Fe^{2+}(aq.)+2e^-\rightarrow Fe(s)[/tex]
Hence, the half reaction that describes the reduction reaction is [tex]Fe^{2+}(aq.)+2e^-\rightarrow Fe(s)[/tex]
