The reaction at the cathode in the cells comm | vedclass

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Question

(A) The cells commonly used in clocks are mercury cells or zinc-carbon dry cells. In these cells,the cathode reaction involves the reduction of mangan

Vedclass · Accepted Answer

reduction of $Mn$ from $+4$ to $+3$

Vedclass · Answer

(A) The cells commonly used in clocks are mercury cells or zinc-carbon dry cells. In these cells,the cathode reaction involves the reduction of manganese dioxide $(MnO_2)$.Specifically,in the dry cell,the reaction at the cathode is: $MnO_2 + NH_4^+ + e^- \rightarrow MnO(OH) + NH_3$.In $MnO_2$,the oxidation state of $Mn$ is $+4$. In $MnO(OH)$,the oxidation state of $Mn$ is $+3$.Therefore,the reaction involves the reduction of $Mn$ from $+4$ to $+3$.

The reaction at the cathode in the cells commonly used in clocks involves:

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