How do I calculate the cell potential?
1 Answer
Sep 26, 2017
Explanation:
For an in-depth explanation see Ernest Z's answer.
To calculate standard cell potential, you use the formula:
E_(cell)^@=E_(red)^@+E_(o x)^@E∘cell=E∘red+E∘ox ,where
E_(cell)^@E∘cell is the cell potential,E_(red)^@E∘red is the reduction potential andE_(o x)^@E∘ox is the oxidation potential. These are at25^@ "C"25∘C and"1 atm"1 atm .
To calculate cell potential in non-standard conditons, the equation is:
E_(cell)= E_(cell)^@- (RT)/(nF)lnQEcell=E∘cell−RTnFlnQ ,
where
E_(cell)Ecell = cell potential at non-standard state conditionsE_(cell)^@E∘cell = standard state cell potentialRR = universal gas constant ("8.314472 J/mol" cdot "K"8.314472 J/mol⋅K )TT = absolute temperature (Kelvin scale)FF = Faraday's constant ("96485 C/mol e"^-96485 C/mol e− )nn = number of moles of electrons transferred in the balanced equation for the reaction occurring in the cell- Q = reaction quotient for the reaction
aA + bB -> cC + dDaA+bB→cC+dD ,so
Q=([C]^c [D]^d)/([A]^a [B]^b)Q=[C]c[D]d[A]a[B]b
This is the [Nernst equation.](http://www.chem.purdue.edu/gchelp/howtosolveit/Electrochem/Electrochemical_Cell_Potentials.htm)
I hope I helped!