n in -nFE
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n in -nFE
I know that he went over this in class, but can someone explain to me where the n comes from ? Thanks!
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Re: n in -nFE
n is the number of moles and it comes from the fact that the value of Faraday's constant is the charge per mole so that's why you have to multiply it by the number of moles.
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Re: n in -nFE
In the 7th edition of the textbook, the equation is explained on pg. 547. Basically, the change in Gibbs free energy equals the max nonexpansion work of an isobaric and isothermal reaction (). Work is done when electrons move through a potential difference, which it can be calculated by multiplying their total charge with the potential difference. So you need n, the number of electrons in moles, to calculate
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Re: n in -nFE
n is the number of electrons in moles. This can be found by writing the two half-reactions and seeing how many electrons are transferred.
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Re: n in -nFE
n is the moles of electrons, just be sure not to confuse it with the moles of the agents. you can figure out the number of moles of electrons by writing both the half reactions and seeing the number of electrons transferred.
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Re: n in -nFE
n represents the moles of electrons. In each balanced half reaction, the number of moles of electrons should be the same, but on different sides of the reaction.
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Re: n in -nFE
In this particular case, since we're trying to talk about charge, n is the number of moles of electrons
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Re: n in -nFE
Be aware that since an equation is composed of two half reaction. You only need to know the moles of electron transferred in one group but not adding up that of both reactions.
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Re: n in -nFE
You need the moles of electrons transferred in a cell in order to cancel out the moles in Faraday's constant (mol x C/mol = C). To find the moles of electrons transferred, you write out both the oxidation and reduction half reactions, balance the reactions so the electrons cancel on both sides, and the coefficient of the electron in the balanced half reactions is your value for n. Review example 6L.1 and 6L.1A on page 685 in the 7th edition textbook for practice.
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Re: n in -nFE
n is the number of moles of electrons, which you can find after balancing the half reactions.
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Re: n in -nFE
You need the moles of electrons transferred in a cell in order to make sure the units cancel out and you get your final answer in the correct units.To find n write out the half reactions to determine the amount of electrons are being transferred. Make sure not to add the electrons from both sides. If one one side you have -2e and the other you have -3e you find the lowest number that would cancel out electrons on both sides. For this example the number would be 6.
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