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## Homework Statement

It's just that in my textbook, for section titled "Second virial coefficients can be used to determine intermolecular potentials," I have an equation that I do NOT understand how it was derived---I tried to do it over and over, but couldn't quite figure how. If anyone could explain, thank you!!!

B

_{2v}(T) = RT * B

_{2p}(T), where B

_{2v}(T) and B

_{2p}(T) are virial coefficient

## Homework Equations

B

_{2v}(T) = RT * B

_{2p}(T), where B

_{2v}(T) and B

_{2p}(T) are virial coefficient

## The Attempt at a Solution

I assume the equation comes from Z, the compressibility factor:

Z = PV/RT, where it can be expanded to:

Z = 1 + B

_{2v}(T)/V + B

_{3v}(T)/V

^{2}+ ...

Z = 1 + B

_{2p}(T)*P + B

_{3p}(T)*P

^{2}+ ...

So, I equivocated 1 + B

_{2v}(T)/V + ... = 1 + B

_{2p}(T)P + ...

B

_{2v}(T)/V + ... = B

_{2p}(T)P + ...

...and tried multiplying both side by V or divide by P to cancel out other virial coefficients with numbers larger than 2 (meaning B

_{3v}and B

_{3p}), but I don't know how to progress anymore.......pls give me hints! I want to understand how the original equation B

_{2v}(T) = RT * B

_{2p}(T) was obtained!