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.
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.
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 !