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5 votes
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Deriving Nernst Equation for a hydrogen-oxygen Fuel cell

Rather than pointing whether the assumptions are correct or incorrect, I will show you a general method to obtain the Nernst's equation for any system. It is a more systematic and formal approach, ...
Metal Storm's user avatar
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3 votes

How exactly does the Nernst equation account for temperature?

There are two temperature dependences involved in the Nernst equation. The explicit one $$\frac{RT}{nF}\ln{a}\tag{1}$$ and the implicit one $$\begin{align} E^\circ(T) &= \frac{-\Delta_\mathrm rG^\...
Poutnik's user avatar
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2 votes

Effect of temperature on voltage of a galvanic cell can't use Nernst equation?

TL;DR; version: Testing the EMF dependence on temperature does make sense, because it is not the matter just of the term $\dfrac{RT}{nF} \ln {Q}$. But you cannot use the Nernst equation directly as ...
Poutnik's user avatar
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2 votes
Accepted

Inconsistency in between Nernst Equation and Gibbs Free Energy Equation

Rather than being an inconsistency, it has to do with the freedom of choosing a mathematical expression for the chemical potential that is more convenient to you. A general expression for the chemical ...
Metal Storm's user avatar
  • 3,546
2 votes

Can an electrode run out of the active species?

Yes, it will absolutely run out. To put it simply, this is a battery, and it will run out of juice like any other battery. You're also correct about which reactant would run out first. The hydrogen ...
anon's user avatar
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1 vote

How to deduct the concentration of chloride in a silver/silver chloride electrode, given the cell notation

The cell notation doesn't indicate, nor limit the shape of the electrochemical cell. In the form used by you, it only describes a zinc electrode in a (presumed aqueous) solution of $\ce{ZnCl2}$ ($c = ...
Buttonwood's user avatar
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1 vote

Why is there a need to have Hâ‚‚(g) gas even at the cathode of SHE (standard Hydrogen electrode) / Galvanic cell?

Note that SHE is intended to operate at practically currentless mode, safe the negligible input current of the voltmeter. So the reactions $\ce{Zn(s) -> Zn^2+(aq) + 2 e-}$ on the zinc anode $\ce{2 ...
Poutnik's user avatar
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