If we plot P vs. 1/V, then do we get a straight line?

1 Answer
Mar 20, 2017

We don't, unless the temperature is fixed. For simplicity, this is certainly true for ideal gases. The ideal gas law is:

PV=nRT

Solving for pressure we get:

P=(nRT)1V

Since mols n, the universal gas constant R, and T are held fixed intentionally, if we chose to make a graph of P vs. 1V, it is linear. That's a mathematical result of forcing nRT to be a constant.

It is of the form y=mx+b where x=1V, b=0, and m=nRT. Mind you, if you chose to plot P vs. V you would not see a straight line. What would you see instead?