Concept explainers
Interpretation:
The emf of a given galvanic cell has to be calculated.
Concept introduction:
Standard reduction potential: The voltage associated with a reduction reaction at an electrode when all solutes are 1M and all gases are at 1 atm. The hydrogen electrode is called the standard hydrogen electrode (SHE).
Standard emf: Eocell is composed of a contribution from the anode and a contribution from the cathode is given by,
Where both
Effect of concentration on cell Emf:
The mathematical relationship between the emf of galvanic cell and the concentration of reactants and products in a
As known
Dividing by –nF, the above equation becomes,
Nernst equation: The Nernst equation is used to calculate the cell voltage under nonstandard-state conditions.
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Chemistry
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