Concentration Cells

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Jessica Castellanos
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Concentration Cells

Postby Jessica Castellanos » Sun Mar 08, 2020 6:52 pm

Can someone explain how electron transfer in concentration cells occurs?

Ariana Iranmahboub1G
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Joined: Fri Aug 09, 2019 12:17 am

Re: Concentration Cells

Postby Ariana Iranmahboub1G » Sun Mar 08, 2020 7:02 pm

In a concentration cell, the two half-cells have the same electrodes. However, the concentrations in each half-cell is different. As the cell reaches equilibrium, electrons from the cell with the lower concentration are transferred to the cell with the higher concentration, creating a voltage. When the cell, reaches equilibrium, there is no longer any voltage so the standard cell potential equals zero.

Ashley Nguyen 2L
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Re: Concentration Cells

Postby Ashley Nguyen 2L » Mon Mar 09, 2020 12:21 pm

A concentration cell has the same anode and cathode, which means that electron transfer comes from differences in concentration. When the two electrodes are connected, electrons from the cell with the lower concentration (the anode) move to the cell with the higher concentration (cathode) to create a voltage. Additionally, because this is a concentration cell, Enot will always equal zero because there is no potential difference between both sides, as they are both the same electrode. Only Ecell would change because of the Nernst equation because it is concentration dependent.

Long Luong 2H
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Joined: Thu Sep 19, 2019 12:16 am

Re: Concentration Cells

Postby Long Luong 2H » Mon Mar 09, 2020 4:37 pm

In a concentration cell, the chemical species involved have the same element but different concentrations. When electrons from a lower concentration solution travel across the electrode, a voltage is generated. When the electrons arrive at the cathode of higher concentration, it attracts ions of the solution and forms on the cathode, essentially lowering the concentration of the solution.

Return to “Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)”

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