[chelovek]

I have a problem where I am given an equation of state pV=RT+(bRT-a)/V and asked to find the work produced in the isothermal, reversible expansion from V1 to V2.

I thought I would want to use W=-integral(nRT/V)dV, but that is apparently only for ideal gases, and this problem concerns a non-ideal gas, according to my professor.

1) How do I know by looking at the problem that this doesn't concern an ideal gas. (the equation given does look like the van der Waals equation...)
2) Since it isn't an ideal gas, what equation can I use? w=-integral(Pext*dV)?
.
Any ideas? I'm feeling really lost here conceptually

[Yggdrasil]

1) For an ideal gas, the equation of state is pV = nRT.  Since your equation of state is different than this, your gas is not ideal.

2) Yes.  You can derive an expression for P in terms of V using the equation of state. 

(this is essentially what happens in the ideal gas case since P = nRT/V for an ideal gas, this means that W = -Integral[(nRT/V)dV])

[chelovek]

Ah, thanks man. I had been stuck on this all day.