finding "n"

[Kaylee Nezwek 1D]

hey! I'm getting a bit confused on how to find "n" when using the Nernst equation or calculating K. does it refer to the number of the moles, or the number of electrons transferred?

for example, in solving for K for the reaction Mn (s) + Ti^2+ (aq) --> Mn^2+ (aq) + Ti (s), in the solutions manual n=2. I wasn't sure if this represented moles or the two e- transferred in each half-rxn. For the reaction In^3+ (aq) + U^3+ (aq) --> In^2+ (aq) + U^4+ (aq), n was also = 2, even though for the half-rxns, only one e- was transferred. can anyone explain why n=2 for these reactions/how to determine n?

[Alexis Sanft 1E]

n is found by the number of moles of electrons being transferred. You have to make sure the number of electron transfer is balanced though by balancing both electron count for the half reactions.

[Keerthana Sundar 1K]

hey! I'm getting a bit confused on how to find "n" when using the Nernst equation or calculating K. does it refer to the number of the moles, or the number of electrons transferred?

for example, in solving for K for the reaction Mn (s) + Ti^2+ (aq) --> Mn^2+ (aq) + Ti (s), in the solutions manual n=2. I wasn't sure if this represented moles or the two e- transferred in each half-rxn. For the reaction In^3+ (aq) + U^3+ (aq) --> In^2+ (aq) + U^4+ (aq), n was also = 2, even though for the half-rxns, only one e- was transferred. can anyone explain why n=2 for these reactions/how to determine n?

In the first example you stated, the n=2 represents the two e- transferred in each half-rxn, as you mentioned. For the second reaction you mentioned, are you sure the textbook did not make a typo or the reaction was typed wrong? The electrons transferred should be the value of n, so in the example you provided, it should be n = 1.

[Ken_Cheng_2A]

Other people asked questions about this particular textbook problem, and it was revealed that the solutions manual has a typo. For the reaction with In^3, it should be n=1, as Keerthana explained.

[shevanti_kumar_1E]

n refers to the moles of electrons transferred in the balanced redox reaction.

[Aditya Sundaram 3D]

First, you can use a balanced redox equation. Once you have that you can count the electrons being transferred and that should give you n.

[Will Skinner]

N represents the number of moles of electrons transferred. You are correct about the n in your first example, but for the second equation if the textbook uses n=2 it must be a typo. It should be 1.

Also, always remember to balance the half reactions before determining n.

[Lillian]

n refers to the number of moles of electrons transferred. So to find it, balance the redox reactions :)

[Rachael Cohen 3G]

n is the number of moles of electrons being transferred in the reaction.

[Sean Wang 1F]

N is the amount of electrons transferred in the redox reaction. Make sure to scale the equations so that the electrons transferred in both half reactions are the same.

[Evelyn Silva 3J]

N is the number of electrons being transferred after balancing the reduction and oxidation reactions

[Ziyan Peng 3A]

n is the number of electrons in the balanced equation.

[Eve Gross-Sable 1B]

Yes, so the "number" and moles are going to be the same thing, it's the coefficient next to the electron, but it has to be taken from the balanced reaction instead of the half equations.