Question about n
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Question about n
Does the n depend on the number of moles of the reactants ie. if there is 1 mol of e- transferred per one mol of the reaction and there are only .1 mols of reactant, then n = .1? Or is it only dependent on the coefficient/number of moles of e- for one mole of reaction?
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Re: Question about n
Hi! From what I have gathered, n is just the number of electrons being transferred. After balancing the equations and making sure the number of electrons is the same for both, that is your n. For instance, if there are 6 electrons being canceled out between both equations, then n would be 6, not 0.6. Hope this helps!
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Re: Question about n
Yes, the "n" represents the number of electrons that are transferred. This can easily be found by using oxidation numbers. For example,
(Textbook problem 6K.3 (c)
H2S(aq) + Cl2 (g) -> S(s) + Cl-(aq)
We get the oxidation numbers +1, -2, 0, 0, and -1 respectively. Looking at sulfur, it goes from -2 to 0. Since it's going up, it's being oxidized and losing 2 electrons (2-0=2). Looking at Chlorine, it goes from 0 to -1. It's going down so it's being reduced, gaining one electron (0-1=1). Even though these electron values are unequal, you can multiply this reduction half-reaction by 2 such that the two electrons lost are both being gained. So in this case n would equal 2.
(Textbook problem 6K.3 (c)
H2S(aq) + Cl2 (g) -> S(s) + Cl-(aq)
We get the oxidation numbers +1, -2, 0, 0, and -1 respectively. Looking at sulfur, it goes from -2 to 0. Since it's going up, it's being oxidized and losing 2 electrons (2-0=2). Looking at Chlorine, it goes from 0 to -1. It's going down so it's being reduced, gaining one electron (0-1=1). Even though these electron values are unequal, you can multiply this reduction half-reaction by 2 such that the two electrons lost are both being gained. So in this case n would equal 2.
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Re: Question about n
To add onto the other responses, in redox reactions n is not determined by the number of mols in the reactant and products separately, but rather is determined by the number of electrons that are being transferred in a balanced reaction. The number of electrons being transferred for each half-reaction should be the same, so as long as the reaction is balanced then n will have the same for both the oxidation and reduction half-reaction. Hope this helps!
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Re: Question about n
Hi! "n" does not depend on the number of moles of the reactant. "n" refers to the number of electrons transferred. So in the example that you provided, "n" would actually be 1 because there is 1 mol of e- transferred in that reaction.
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Re: Question about n
Hello! n does not rely on the stoichiometric coefficients or moles of reactants. n refers to the number of electrons being transferred in a balanced redox equation. When given half reactions, we must first balance them out in number of electrons and then that number will be our "n".
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Re: Question about n
n can be found after balancing the electrons in the half reaction equation; n is separate from the stoichiometric coefficients in the equation, and contrary to what we have learned about n in regards to other topics, it is not the value of moles, it is rather the quantity of electrons transferred.
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Re: Question about n
Very grateful for this post, previously I had been running under the assumption that n was determined by the number of mols rather than the electrons being transferred in the balanced reaction, which clears up a lot of the previous confusion I had.
Just to check my understanding: If the reaction is balanced, n will be the same for the oxidation and reduction half reaction, and reffers to the amount of electrons being transferred.
Just to check my understanding: If the reaction is balanced, n will be the same for the oxidation and reduction half reaction, and reffers to the amount of electrons being transferred.
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Re: Question about n
Hello, it is important to remember that n is the value of the number of electrons being transferred. You must make sure that the equation is balanced. In your example, n would be 1 since there is one mole of electrons being transferred. I hope this helps:)
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