How is current conducted in a salt solution?

In summary: This prevents the build-up of excess electrons on the cathode and allows the current to flow continuously.
  • #1
Monsterman222
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Imagine you connected the two terminals of a battery to electrodes and stuck them into a salt solution. There would be a current. I realize that the current inside the solution is the flow of the negative Chloride ions towards the cathode and the positive Sodium ions towards the anode. And the current inside the metal electrodes is due to free electron flow.

Am I correct in thinking that the electrons leaving the battery and going towards the cathode do not pass into the solution? If that were the case, would they not just build up on that cathode? It seems that eventually the circuit would grind to a halt when too many electrons were on the cathode, but that's not the case...

Any help?
 
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  • #2
Yes, you are correct in thinking that the electrons leaving the battery and going towards the cathode do not pass into the solution. The electrons will flow through the metal electrodes and the electrolyte solution to form an electric current. This current is caused by the movement of ions within the electrolyte solution. The positive ions, such as sodium, move towards the cathode, while the negative ions, such as chloride, move towards the anode. The electrons leaving the battery are then replaced by electrons from the electrolyte solution, creating a continuous circuit.
 

1. How does current flow through a salt solution?

The flow of current through a salt solution is due to the movement of charged particles, known as ions, in the solution. These ions are created when the solid salt dissolves in water, and they carry an electrical charge. When an electric field is applied to the solution, the positively charged ions (cations) move towards the negative electrode and the negatively charged ions (anions) move towards the positive electrode. This movement of ions constitutes the flow of current in a salt solution.

2. What factors affect the conductivity of a salt solution?

The conductivity of a salt solution depends on several factors, including the concentration of the salt, the type of salt used, the temperature of the solution, and the distance between the electrodes. Generally, a higher salt concentration and warmer temperature will result in a higher conductivity, while a larger distance between the electrodes will decrease conductivity.

3. How does the type of salt used affect the conductivity of a solution?

The conductivity of a salt solution can vary depending on the type of salt used. Some salts, such as sodium chloride, are highly conductive due to their ability to dissociate into ions easily. Other salts, such as calcium chloride, may have a lower conductivity due to the formation of insoluble compounds that decrease the number of ions available to conduct electricity.

4. Can pure water conduct electricity like a salt solution?

No, pure water does not conduct electricity like a salt solution. This is because pure water does not contain any ions that can carry an electrical charge. However, if impurities are present in the water, such as dissolved salts or minerals, it can increase the conductivity of the water.

5. Why is it important to understand how current is conducted in a salt solution?

Understanding how current is conducted in a salt solution is important for various scientific and practical applications. For example, it is essential in electrochemistry, where reactions occur at the electrodes in a salt solution. It also has implications in industries such as water treatment, where the conductivity of a solution can indicate the level of impurities present. Additionally, understanding the conductivity of salt solutions can help in the design and optimization of batteries and fuel cells.

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