What's the difference b/t farad and faraday's constant?

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lotus0618
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What's the difference b/t farad and faraday's constant?

Post by lotus0618 » Thu Mar 19, 2020 9:13 pm

What's the difference b/t farad and faraday's constant? I attached the 2 pictures with this post. thanksss
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NS_Tutor_Mathias
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Re: What's the difference b/t farad and faraday's constant?

Post by NS_Tutor_Mathias » Fri Mar 20, 2020 12:06 am

A Farad is a unit of capacitance. That is all. It does not have units of charge, but rather charge per voltage difference, implying that the same capacitor will hold more charge if a greater potential difference exists, which we know to be true (Q = CV).

But Faraday's constant is a fixed amount of charge - it is really just the amount of charge in a mole of electrons. This comes in handy when we are having to use reduction and oxidation potentials, as those are measured on a per-electron basis. That is why for example deltaG = -nFE looks the way it does. You take the reduction potential (per electron), multiply it by how much charge is in a mole of electrons (F) and then multiply all that by how any electrons you got - and what you get out is how spontaneous (or not) your current electrolytic cell (or reaction in general) happens to be, and with it the ability to predict how long it will continue for.
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