For the first part of my lab, I have a graph with pressure(atm) as a function of temperature(K). For the second part of my lab, I have a graph with pressure(atm) as a function of inverse volume(mL^-1) For both of these, i am supposed to find the value for R, the gas constant. So far far part a i have: PV = nRT P = (nR/V)T (in the form y = mx +b), So the slope of my graph is nR/V I also know that n is kept constant, because it was a closed system and 1mol= 22.4L. And that the initial volume is 20mL. And i think I should I pick two points on the line to find the slope and set that equal to nR/V. And this is where i'm having trouble, i get some value for the slope, m, so m = nR/V R = mV/n, here i'm confused at how to find V and n in order to solve for R. For part b; PV = nRT P = (nRT) 1/V So the slope of my graph is nRT I did the same thing as part one; m = nRT R = m/nT, since T was not chnged, I can do that part, but once again, I am confused by finding n.