Salt bridge maintains electrical neutrality in two compartments by allowing movement of anions towards anodic compartments and cations towards cathodic compartments. It is a glass tube having potassium chloride or ammonium nitrate in a gelatin form.
The functions of the salt bridge are
- A salt bridge acts as an electrical contact between the two half cells.
- It prevents the mechanical flow of solution but it provides a free path for the migration of ions, to maintain an electric current through the electrolyte solution. It prevents the accumulation of charges.
- A salt bridge helps in maintaining the charge balance in the two half cells.
- A salt bridge minimizes or eliminates the liquid junction potential.