According to my textbook

Concentration of anodic half cell increases and that of cathodic half decreases when two electrodes are joined by a wire.

I have also read that it is connected with a Salt bridge which prevents the flow of the electrolyte ions and supplies the required cation or anion (from the inert electrolyte in the salt bridge) and overall its electrically neutral . Then how they can state that concentration increases in one half cell only ,that is both cells are provide with sufficient ions ? Please correct me if I am wrong somewhere in understanding the concept.

  • $\begingroup$ Look at the Daniell cell here. The zinc metal anode is oxidized to zinc ions, so the zinc ion concentration in the anode reservoir increases as the cell provides electrical power. Copper ions get reduced at the cathode, so the copper ion concentration is reduced in the cathode reservior. $\endgroup$
    – Ed V
    Jul 14 at 2:03
  • $\begingroup$ @Ed V okay sir , I understood . I was considering anions too , I thought that in cathodic cell there will be accumulation of anions which will increase the concentration of anions there . $\endgroup$ Jul 14 at 2:19
  • $\begingroup$ Cations and anions must be always balanced. Any tiny disbalance would cause strong potential gradient leading to rebalancing. $\endgroup$
    – Poutnik
    Jul 14 at 4:40

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