In a working electrochemical cell, the cations in the salt bridge move toward the cathode.

• A. True
• B. False
• C. Cations move toward the anode
• D. Anions move toward the cathode

Answer: (A)

The salt bridge serves to keep each half-cell electrically neutral as the cell operates. In the cathode compartment, reduction removes positive charge by converting metal ions in solution into solid metal on the electrode, so the solution tends to become deficient in cations. To restore balance, positively charged ions from the salt bridge migrate toward the cathode, carrying positive charge across the bridge. This is why cations move toward the cathode. The accompanying movement of anions toward the anode restores neutrality there as oxidation occurs. So the statement that cations in the salt bridge move toward the cathode is correct.