# Gas Density Equation

1. ### kinogram

24
If the equation below is correct

$n = PV / (R/T)$

where :

n = gas density in mole / m³
P = pressure in Pascal
V = volume in m³
R = ideal (individual) gas constant
T = temperature in Kelvin

Given that the individual gas constant - R for H2 = 4124 J / kg K

Then 1 m³ of H2 at 101325 Pa and 273.15 K
should have a molar density of 0.089949

and

1 m³ of H2 at 5 x 10-18 Pa and 2.7 K
should have a molar density of 4.49 x 10-22

are these calculated results correct?

.

### Staff: Mentor

There is an algebra error in your starting equation... See http://en.wikipedia.org/wiki/Ideal_gas_law

3. ### kinogram

24
Thanks.. I see that now

$PV=nRT$

Then

$n=PV/(RT)$

however it looks like the calculations were made correctly according to the proper equation

.

Last edited: Jul 23, 2014