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I'm currently rereading "An Introduction to Quantum Physics" by A.P. French, and confused myself.

The text reads along the lines of (paraphrased):

Making the assumption that e is equal both to the magnitude of the charge of the electron and also to the smallest charge carried by any individual ion in electrolysis we can find the number of atoms or molecules in one mole - that is, Avogadro's number, N: $$N=\frac{F}{e}=\frac{96,485}{1.6022*10^{-19}}$$

Earlier in the text, it describes a Faraday following:

Faraday's electrolysis experiments provided a value for the amount of charge needed to release a gram-equivalent of any ionic species, called the Faraday, F

Later, it also explains how to find atomic volumes and radii from the found information in solid form.

If the density is $\rho$ and the atomic weight is A the number of atoms per unit volume n is given by $$n=\frac{\rho N}{A}$$ The volume per atom $V_a$ is then equal to $1/n$.

The text then goes on to explain $V_a$ and R by comparing the atoms to a cube, which makes sense. I'm not understanding what exactly a Faraday is in relation to Avogadro's number, and then why volume per atom is related to $1/n$. I'm just a bit confused over everything, perhaps.

Thank you for helping out!

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  • $\begingroup$ The Faraday is the amount of charge on one mole of electrons (or protons). $\endgroup$ – Farcher Nov 25 '18 at 10:01

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