In previous sections when describing cells, we have assumed standard conditions (all concentrations 1 M). If concentrations of any substance are greater than 1 M, we can answer qualitatively with Le Chatelier's principle. An increase in concentration of a reactant will favor the forward reaction and thus increase the driving force on the electrons, which increases the cell potential. An increase in concentration of a product will oppose the forward reaction and thus decrease the driving force on the electrons, which decreases the cell potential.
A certain type of galvanic cell called a concentration cell can be constructed. This is a cell in which both compartments have the same components but at different concentrations. To solve this problem, we need to recognize that nature will try to equalize the concentrations in the compartments and transfer electrons from the compartment of lower concentration to the compartment of higher concentration.
Another equation that is necessary is the Nernst equation, which is:
E = E° - RT/nF ln (Q)
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