I'm doing a study a study on voltaic cells. I've been working with them for a while and one of the questions that I've had is how does the salt bridge affect the cell. I mean, I know it allows ions to move and that it'a a basic component of the pill. But, does its' concentration affect the voltage of the cell itself? Thank you.
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A n ideal salt bridge just eliminates liquid-liquid junction potential without affecting the equilibrium of the cell. A non ideal salt bridge changes the observed voltage depending on the relative mobilities of the ions in the salt bridge solution. – stochastic13 Feb 06 '14 at 11:07
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A cell has an internal ohmic-equivalent resistance. The salt bridge is a resistive path for the flow of ions. Ions, plus their hydration shells and possible coordination shells, have low drift velocities through a medium. The salt bridge can constrain the ion current of the cell and its material equilibrium rate. A poor salt bridge by length, diameter, concentration, and permeability will increasingly adversely affect a cell's current and voltage as discharge rate increases.

Uncle Al
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I don't think it affects the voltage of the cell as : E°(cell)= E°(red,cathode) - E°(red,anode) so it doesn't depend on the salt bridge !

Samah
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Theoretically it does not, although many factors ensure the observed voltage is lower than the theoretical voltage including the resistance of the salt bridge. – Nasser Kessas Mar 20 '23 at 00:08