The potential difference between the electrode and the electrolyte in an electrochemical cell is called electrode potential.

The cell drawn above represents electrochemical cell in which two different electrodes are fitted in their respective electrolytic solution and cell drawn at bottom represents electrolytic cell.

Cell representation can be represented as $\mathrm{Zn}\left|\mathrm{Zn}^{2+} \| \mathrm{Cu}^{2+}\right| \mathrm{Cu}$.

Zn is loosing electrons which are going towards electrode (A) and copper is accepting electron from electrode B. Hence,

Charge on electrode $A=+$

Charge on electrode $B=-$

Alternating current is used in electrolysis so that concentration of ions in the solution remains constant and exact value of resistance is measured.

When an opposing potential of 1.1 V is applied to a galvanic cell having electrical potential of 1.1 V then cell reaction stops completely and no current will flow through the cell.

The pH of the solution will rise as NaOH is formed in the electrolytic cell. Chemical reaction occurring at cell when aqueous brine solution is electrolysed are as follows

$$\begin{aligned} & \mathrm{NaCl}(a q) \xrightarrow{\mathrm{H}_2 \mathrm{O}} \mathrm{Na}^{+}(a q)+\mathrm{Cl}^{-}(a q) \\ & \text { Cathode } \mathrm{H}_2 \mathrm{O}(l)+e^{-} \longrightarrow \frac{1}{2} \mathrm{H}_2(g)+\mathrm{OH}^{-}(a q) \\ & \text { Anode Cl }(a q) \longrightarrow \frac{1}{2} \mathrm{Cl}_2(g)+e^{-} \\ \text{Net reaction}\quad& \mathrm{NaCl}(a q)+\mathrm{H}_2 \mathrm{O}(l) \longrightarrow \mathrm{Na}^{+}(a q)+\mathrm{OH}^{-}(a q)+\frac{1}{2} \mathrm{H}_2+\frac{1}{2} \mathrm{Cl}_2 \end{aligned}$$