1. Maintain Electrical Neutrality: The half-reactions occurring at the electrodes generate ions. Without a salt bridge, the build-up of these ions in the respective half-cells would create a charge imbalance, stopping the flow of electrons and halting the cell's operation. The salt bridge allows ions to migrate from one half-cell to the other, counteracting the charge build-up and ensuring electrical neutrality.
2. Complete the Circuit: While electrons flow through the external circuit (the wire connecting the electrodes), ions need a path to travel within the cell itself. The salt bridge provides this pathway, allowing ions to move between the half-cells and complete the circuit.
In short, the salt bridge acts as a conduit for ion flow, maintaining charge balance and allowing the electrochemical cell to operate efficiently.
