In an electrochemical cell,

Which of the following statements is correct regarding the cathode of an electrochemical cell?

What are the common uses of a dry cell?

If the salt bridge between two half-cells is removed,the voltage of the cell:

Given that
$E^o_{Ni^{2+} | Ni} = -0.25 \ V$
$E^o_{Cu^{2+} | Cu} = 0.34 \ V$
$E^o_{Ag^{+} | Ag} = 0.80 \ V$
$E^o_{Zn^{2+} | Zn} = -0.76 \ V$
Which of the following reactions under standard condition will not take place in the specified direction?

For a $Ag-Zn$ button cell,the net reaction is $Zn_{(s)} + Ag_{2}O_{(s)} \rightarrow ZnO_{(s)} + 2Ag_{(s)}$. Given $\Delta G_{f}^{o}(Ag_{2}O) = -11.21 \ kJ \ mol^{-1}$ and $\Delta G_{f}^{o}(ZnO) = -318.3 \ kJ \ mol^{-1}$,the $E^{o}_{cell}$ of the button cell is ......... $V$.