Which of the following statements is correct? $A$ galvanic cell converts:

Give the chemical reaction when a $Cu$ rod is kept in an $AgNO_{3}$ solution.

Write the cell reaction of a lead storage battery when it is discharged. How does the density of the electrolyte change when the battery is discharged?

$Cu^{+}_{(aq)}$ is unstable in solution and undergoes simultaneous oxidation and reduction,according to the reaction $2 Cu^{+}_{(aq)} \rightleftharpoons Cu^{2+}_{(aq)} + Cu_{(s)}$. Choose the correct $E^{\circ}$ for the above reaction if $E^{\circ}_{Cu^{2+}/Cu} = 0.34 \ V$ and $E^{\circ}_{Cu^{2+}/Cu^{+}} = 0.15 \ V$.

Some statements about Leclanché cell are:
$(I)$ Anode is zinc metal
$(II)$ Cathode is graphite rod surrounded by powdered $MnO_2$ and carbon
$(III)$ Electrolyte is a moist paste of $ZnO$ and $KOH$
$(IV)$ Oxidation product is $ZnO$
The correct statements are:

Which of the following is an incorrect statement?