# How do you calculate molar volume of oxygen gas?

May 15, 2014

Using the Ideal Gas Law, you would find the volume of 1 mole of a gas at Standard Temperature and Pressure (STP).

STP = 1 atm of pressure and 273 K for temperature

P = 1 atm
V = ???
n = 1 mole
R = 0.0821 atm L/mol K
K = 273 K

$P V = n R T$
solves to
$V = \frac{n R T}{P}$

$V = \frac{1 m o l \frac{0.0821 \left(a t m L\right)}{m o l K} 273 K}{1 a t m}$

V = 22.41 L of gas @ STP
This is also known as Avogadro's number for molar volume of a gas @ STP