What is the primary function of a salt bridge in an electrochemical cell?

The primary function of a salt bridge in an electrochemical cell is to maintain charge balance by allowing ion flow. In an electrochemical cell, oxidation occurs at the anode and reduction at the cathode, which leads to a build-up of positive charge in one half-cell and a build-up of negative charge in the other. This charge imbalance can halt the flow of electrons if not addressed.

The salt bridge contains a salt solution and is designed to allow the migration of ions between the two half-cells. For example, positively charged ions (cations) from the salt bridge can flow into the half-cell where negative charge is accumulating, while negatively charged ions (anions) can flow into the half-cell where positive charge is building up. This ion flow helps to neutralize the charge differeneces, thus maintaining the electrochemical reaction and allowing the cell to continue functioning effectively.

While other options mention aspects related to the operation of an electrochemical cell, they do not correctly describe the unique role of the salt bridge in charge balance. The pathway for electron flow is typically through the external circuit, while the enhancement of voltage relates to the composition of the cell and its materials—not the function of the salt bridge. Similarly, preventing oxidation at the electrodes