How do you find the ideal gas constant?

1 Answer
Mar 20, 2014

The ideal gas law uses the formula PV = nRT where P is the pressure in atmospheres (atm), V is the volume in liters (L), n is the number of moles (mol) and T is the temperature in kelvin (K).

If we set up the ideal gas law for the values of 1 mole at Standard temperature and pressure (STP) and calculate for the value of the constant R, we can determine the value of the ideal gas law constant.

P = 1 atm
V = 22.4 L (Avogadro's number)
n = 1 mol
R = Constant
T = 273 K (0 C)

Isolating the R value the equation is

#(PV)/(nT) = R#

#((1 atm)(22.4 L))/((1 mol)(273K))= 0.08205 ((atm)(L))/((mol)(K))#

I hope this was helpful.