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Postby 104969854 » Thu Feb 22, 2018 6:25 pm

For the example int he textbook :
The potential of the Daniell cell for solutions of 1.00 mol/L copper and zinc ions is +1.04 V. What is the reaction Gibbs free energy for this cell?
How did we know that n=2?
In general, do we find n for any reaction? and do we HAVE to find the balanced reaction?

Also, what would n be in the example problem:
The reaction taking place in a nicad (nickel–cadmium) cell is Cd(s) + 2 Ni(OH)3(s) ==> Cd(OH)2(s) + 2 Ni(OH)2(s), and the cell potential when fully
charged is +1.25 V. What is the reaction Gibbs free energy?

Will someone just break down the process of finding n here ? I'm confused because there arent really explicit charges to observe!!
Last edited by 104969854 on Thu Feb 22, 2018 6:46 pm, edited 2 times in total.

Vincent Tse 1K
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Re: n

Postby Vincent Tse 1K » Thu Feb 22, 2018 6:44 pm

I believe n is the # of electrons involved in the balanced redox reaction. I don't particularly know if you necessarily HAVE to find the balanced equation to figure out n, but it's certainly one of the easiest ways to. Just write out the half reactions!

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Re: n

Postby CalebBurns3L » Fri Feb 23, 2018 12:21 pm

Write out the half reactions, and balance them so that the electrons on each side would cancel. Then use the number of electrons that are being transferred as n.

Emma Miltenberger 2I
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Re: n

Postby Emma Miltenberger 2I » Fri Feb 23, 2018 1:03 pm

N is the number of electrons transferred in the reaction. To find this value, write out the half reactions and balance them so the number of electrons gained equals the number of electrons lost. This is the value of n you should use in the equation.

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