Concept:A salt bridge acts as an electrical connection between two half-cells in a galvanic (voltaic) cell, maintaining electrical neutrality.
Solution:- During the operation of a voltaic cell, oxidation occurs at the anode (generating positive ions) and reduction at the cathode (depleting positive ions).
- If this charge imbalance is not neutralized, the cell potential quickly drops to zero.
- The salt bridge allows the flow of spectator ions between the two half-cells to balance this charge without allowing the bulk solutions to mix.
Why other options are incorrect:The salt bridge does not pass electric current (electrons travel through the external wire). It does not prevent ion flow, but rather facilitates it. It specifically exists to
prevent the physical mixing of the two reactive solutions.
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