For the cell $Cu_{(s)} | Cu^{2+}_{(aq)} (1 \ M) || Zn^{2+}_{(aq)} (1 \ M) | Zn_{(s)}$,given $E^{\circ}_{Zn^{2+}/Zn} = -0.76 \ V$ and $E^{\circ}_{Cu^{2+}/Cu} = 0.34 \ V$,the cell reaction is:

Which of the following reactions occurs at the cathode of a common dry cell?

Which metal oxide decomposes upon heating?

Under what condition is $E_{cell} = 0$ or $\Delta_r G = 0$?

The following limiting molar conductivities are given as:
$\lambda_{m(H_{2}SO_{4})}^{0} = x \ S \ cm^{2} mol^{-1}$
$\lambda_{m(K_{2}SO_{4})}^{0} = y \ S \ cm^{2} mol^{-1}$
$\lambda_{m(CH_{3}COOK)}^{0} = z \ S \ cm^{2} mol^{-1}$
The $\lambda_{m}^{0} \ (\text{in } S \ cm^{2} mol^{-1})$ for $CH_{3}COOH$ will be:

From a solution of $CuSO_4$,the metal used to recover copper is