Universal gas constant R

This depends on the units of the measurements used in the ideal gas equation PV=nRT

R then equals PV/nT

If n equals one (for one mole of gas) then

R = PV/T

Using SI units

pressure is measured in Nm-2 and the value at atmospheric pressure is 1.01 x 105

temperature is measured in Kelvin = 273 at STP

volume in SI units 22.41 dm3 = 2.241 x 10-5 m3

R = PV/T = (1.01 x 105 x 2.241 x 10-5) /273

R = 0.00829

When P is measured in atimospheres, and V is measured in dm3

R = PV/T

R = 1 x 22.41 / 273

R = 0.0821