galvanic cell

 

Working of Galvanic Cell

• In a galvanic cell, when an electrode is exposed to the electrolyte at the electrode-electrolyte interface, the atoms of the metal electrode have a tendency to generate ions in the electrolyte solution leaving behind the electrons at the electrode. Thus, making the metal electrode negatively charged.
• While at the same time metal ions in the electrolyte solution too, have a tendency to deposit on a metal electrode. Thus, making the electrode positively charged.
• Under equilibrium condition, charge separation is observed and depending on the tendencies of two opposing reactions, the electrode can be positively or negatively charged. Hence, a potential difference is developed between the electrode and electrolyte.
• This potential difference is known as electrode potential.
• Out of two electrodes, the electrode at which oxidation takes place is called anode while the electrode at which reduction takes place is called cathode.
• The anode has a negative potential with respect to the solution while the cathode has a positive potential with respect to the solution.
• Thus, a potential difference develops between two electrodes of the galvanic cell. This potential difference is known as cell potential.
• When no current is drawn from the galvanic cell, cell potential is known as the electromotive force of the galvanic cell.
• When the switch is set on, due to the potential difference, electrons flow from the negative electrode to the positive electrode.