The ov erall reaction in an electrochemical cell is \(Mg _{(51} \cdot Cu _{(\text {(a) })}^{2+} \rightarrow Mg _{( aq )}^{2+}+ Cu _{( s )}\) * What is the symbolic representation of the cell?
A. \(Mg _{k}, Mg _{\text {(aq) }}^{2+} \| Cu _{(a-1)}^{2 *} / Cu _{(3)}\) B. \(M _{ g _{n i 1}} / Mg _{(i)}^{2+} \| Cu _{( s )}^{2+} / Cu _{(\text {aq })}\) C. \(Cu _{(\text {aq }}^{2+} / Cu _{(s)} \| Mg _{(s)} / Mg _{(\text {(a) }}^{2+}\) D. \(Cu _{( s )} / Cu _{( sq )}^{2+} \| Mg _{( aq )}^{2+} / Mg _{(s)}\)
Correct Answer: A
Explanation
The general symbolic representation of an electrochemical cell is Anode/Anode electrolyte//cathode electrolyte/ cathodeor the reaction $$ Mg _{(s)}+ Cu _{(a+)}^{2+} \rightarrow Mg _{(a q)}^{2+}+ Cu _{(\times)} $$ The half - cell reactions are \begin{aligned} & Mg _{(s)} \rightarrow Mg _{(a q)}^{2+}+2 e ^{-}\left(\begin{array}{c} \text { anode/mg } \\ \text { electrode } \end{array}\right) \\ & Cu _{(a q)}^{2+}+2 e ^{-} \rightarrow Cu _{(s)}\left(\begin{array}{c} \text { cathode/Cu } \\ \text { electrode } \end{array}\right) \end{aligned} The symbolic representation is thus: $$ M g_{(s)} / Mg _{(\text {map })}^{2+} / / Cu _{(\dot{a})}^{2+} / C u_{(x)} $$