# Homework Help: Help graphing a P-V diagram by hand for physical chemistry

1. Sep 11, 2008

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1. The problem statement, all variables and given/known data
A,B,a are constants. sketch two or more isotherms on a P-V diagram. V needs to be the independent variable. Mark clearly the intercepts and asymptotes. One graph for a p -->0 and one graph for p--> infinity.

2. Relevant equations
V=Vo (1-AP/(B+P))(1+ aT)
y=mx+b

3. The attempt at a solution
The last line of the question says no calculations are needed but that feels impossible...The first thing that went through my mind is, since the equation is linear, it should be easy to graph if i made it look like the equation of a line, so i distributed and altered the equation a bit but eneded up w/ a huge mess. I'm stuck bc, i know that for a gas pressure and volume are inversely proportional right? drawing an isotherm for a gas is simple, but for a liquid i have no idea where to begin...Can I get hints into the right direction? T should be constant because it is the isotherm in the graph right?

the point of avoiding the calculations is to just be able to indicate the trends on the graph based on the equation, how do i do that?