Which of the following species acts as a reducing agent during the working of a hydrogen-oxygen fuel cell?

The reference electrode,specifically the Saturated Calomel Electrode $(SCE)$,is made from which of the following substances?

Using the standard electrode potentials given in Table $3.1$ of the $NCERT$ textbook,predict if the reaction between the following is feasible:
$(i)$ $Fe^{3+}_{(aq)}$ and $I^{-}_{(aq)}$
$(ii)$ $Ag^{+}_{(aq)}$ and $Cu_{(s)}$
$(iii)$ $Fe^{3+}_{(aq)}$ and $Br^{-}_{(aq)}$
$(iv)$ $Ag_{(s)}$ and $Fe^{3+}_{(aq)}$
$(v)$ $Br_{2(aq)}$ and $Fe^{2+}_{(aq)}$

In which of the following solutions will a blue color appear after some time when a piece of $Cu$ metal is added?

What will occur if a block of copper metal is dropped into a beaker containing a solution of $1 \ M \ ZnSO_4$?

The cell reaction $Cu + 2Ag^{+} \to Cu^{+2} + 2Ag$ is best represented by