do electrolytic cells require a salt bridge?

[Graffiti]

Do electrolytic cells require a salt bridge? Some books seem to include one, others don't. TBR includes an anion membrane. I know the salt bridge completes the electrical circuit for galvanic cells. Wouldn't this also be true for electrolytic cells even though a battery is powering the electric current?

another question is do the oxidized atoms (cations) navigate through the salt bridge to the cathode or is it only the cations contained in the salt bridge that navigate to the cathode? or both?

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[Mcat35]

Do electrolytic cells require a salt bridge? Some books seem to include one, others don't. TBR includes an anion membrane. I know the salt bridge completes the electrical circuit for galvanic cells. Wouldn't this also be true for electrolytic cells even though a battery is powering the electric current?

another question is do the oxidized atoms (cations) navigate through the salt bridge to the cathode or is it only the cations contained in the salt bridge that navigate to the cathode? or both?

Cation go to cathode, anion go to anode from the salt bridge in-order to balance out the excess charge from oxidation reduction process. If you did not have a salt bridge than the electrons would stop flowing to the cathode because there will be an excess of negative charge there.

For example if you had Zn metal in Zn2+ / So42- solution at the anode and Cu Metal in Cu2+ / So42- solution cathode, and KCl in salt bridge the K+ would flow to the cathode to combine with So42- and Cl- would go to anode to join with the Zn2+ there, therefore there will not be an accumulation of charge and the reaction can keep on going until the salt bridge gets depleted.

Only ions in the salt bridge migrate.

For a electrolytic cell, it would not have a problem because it is non spontaneous, and driven by a battery. there is no charge to balance since the the cathode and anode are in the same solution. cathode is connected to the negative terminal of the battery and it will attract Cations. Anode is connected to the positive terminal and it will attract anions. Electrons will still flow to the Cathode.

For example NaCl solution Na+ would go to cathode and get reduced to Na (l) and Cl- will get oxidized to Cl2(g) at anode.

Note the difference in that anode is positive in electrolytic cells and negative in galvanic cells.