Question

How do you calculate molar volume of oxygen gas?

Answer 1

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 = (n R T )/ P`

`V = (1 mol (0.0821 (atm L))/(mol K) 273 K)/(1 atm)`

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

I hope this was helpful.
SMARTERTEACHER