Salt bridge and electical field

In summary, a salt bridge in a Galvanic cell ensures that there is no electrical field between the solutions of the two half cells. This results in an electrical potential of zero in an ideal world. It is also possible to calculate the difference in electrochemical potential between the solutions by using two electrodes immersed in a single beaker containing an electrolyte.
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wnvl2
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Is it correct that a salt bridge in a Galvanic cell makes that there is no electrical field between the solutions of the two hallf cells? Does that mean that the electrical potential (I do not write electrochemical potential) between both solutions is zero in an ideal world?

Is it also possible to calculate the difference in electrochemical potential between both solutions. I mean the solutions not the electrodes in the solutions. How should that be done?
 
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wnvl2 said:
Is it correct that a salt bridge in a Galvanic cell makes that there is no electrical field between the solutions of the two hallf cells? Does that mean that the electrical potential (I do not write electrochemical potential) between both solutions is zero in an ideal world?
The solutions and salt bridge are 'conductors', except + and - ions carry charge.

In general "The electric field inside the conductor is zero. (Any net electric field in the conductor would cause charge to move since it is abundant and mobile. This violates the condition of equilibrium: net force = 0.)" http://hyperphysics.phy-astr.gsu.edu/hbase/electric/gausur.html#c2

See the discussion here:
https://chem.libretexts.org/Courses...ELECTRO-CHEMISTRY/17.1:_Electrochemical_Cells
Galvanic cells can have arrangements other than the examples we have seen so far (with a salt bridge). For example, the voltage produced by a redox reaction can be measured more accurately using two electrodes immersed in a single beaker containing an electrolyte that completes the circuit. This arrangement reduces errors caused by resistance to the flow of charge at a boundary, called the junction potential.
 
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Related to Salt bridge and electical field

1. What is a salt bridge and how does it work?

A salt bridge is a device used in electrochemistry to maintain electrical neutrality in a galvanic cell. It consists of an inert electrolyte solution (usually a salt) that connects the two half-cells of the cell. The salt bridge allows ions to flow between the two half-cells, balancing out any charge imbalances that may occur during the redox reaction.

2. Why is a salt bridge necessary in a galvanic cell?

Without a salt bridge, a galvanic cell would eventually stop producing electricity due to the buildup of charge imbalances in the two half-cells. The salt bridge allows ions to flow and maintain electrical neutrality, allowing the cell to continue producing electricity.

3. How does a salt bridge affect the electrical field in a galvanic cell?

The salt bridge does not directly affect the electrical field in a galvanic cell. However, it indirectly helps to maintain a constant electrical potential between the two half-cells, which is essential for the cell to continue producing electricity.

4. Can any salt be used as a salt bridge?

No, not all salts can be used as a salt bridge. The salt used must be an electrolyte, meaning it must dissociate into ions in solution. Commonly used salts for salt bridges include potassium chloride and sodium sulfate.

5. How do you know when a salt bridge needs to be replaced?

A salt bridge may need to be replaced if it becomes clogged or contaminated, preventing the flow of ions between the two half-cells. This can be observed if the cell stops producing electricity or if there is a significant change in the cell's electrical potential. It is recommended to regularly check and replace the salt bridge if necessary to ensure the proper functioning of the galvanic cell.

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