Definition - What does Salt Bridge mean?
A salt bridge refers to a device used to form an electrochemical cell by providing a means to support the free flow of ions between the oxidation and reduction half-cell components. A salt bridge facilitates corrosion because corrosive reactions typically occur in the presence of electrochemical cells.
Corrosionpedia explains Salt Bridge
The salt bridge is a key component of any voltaic or galvanic electrochemical cell. Typically, it is a tube filled with electrolytic solutions such as potassium chloride (KCl) or other chlorides. The bridge serves the purpose of keeping the cell electrically neutral and allowing the free flow of ions through its entirety, which prevents electron build-up in the half-cells that would result in halted reactions.
In empirical settings, the salt bridge is often an inverted glass U-shaped tube filled with sodium chloride. Its two legs dip into two separate vessels of electrolyte (the half-cells) to form an electrochemical cell.