Find Work of Isothermal Expansion: Questions Answered

AI Thread Summary
The discussion centers on calculating the work of a reversible isothermal expansion using the provided equation of state for argon, pV=RT(1+B/V +C/V^2). The user questions whether the equation requires subscripts for initial and final volumes and if they can apply ideal gas principles despite the equation indicating non-ideal behavior. It is clarified that the pressure can be expressed as p=RT(1/V+B/V^2 +C/V^3), and the work can be calculated by integrating pdV. The final expression for work is provided, showing how to incorporate the initial and final volumes into the calculation. The discussion concludes with a focus on correctly applying the equation to determine the work done during the expansion.
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have a question.
the viral eqn of state for one mole of aragon is:

pV=RT(1+B/V +c/V^2)

T is known and so is B and C. but p is not known.
initial V is known and so is final V.

the question is "find out the work of a reversible isothermal expansion at this temperature"

Know I'm wondering is there something wrong with the eqn. is there suppose to be some subscripts for inital and final on the V? or am i suppose to figure out a way of rearranging or exchanging part of the eqn with other stuff?

can I exchange stuff that would normally describe an ideal gas?.. it doesn't say that it acts ideal and by the first eqn it doesn't seem as it does. so...
if the eqn is correct do i need to know V?

edit: oki if a move the v over to the left and then integrate.. do i get work or do i have to put something else in there... W=integral of pdV

ps: sorry for posting in the wrong forum.. now the homework. but donät know how to delete it.. if someone could please move it or something.. thanx
 
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From the specified equation of state, the pressure is given by ##p=RT(1/V+B/V^2 +C/V^3)##. Integrating pdV to get the work then gives $$W=RT\left(\ln{(V_f/V_i)}+B(\frac{1}{V_i}-\frac{1}{V_f})+\frac{C}{2}(\frac{1}{V_i^2}-\frac{1}{V_f^2})\right)$$
 
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