According to ChemTeam, molar volume is the volume taken up by one mole of ideal gas at a standard temperature and pressure. It has a of value of 22.414 liters per mole.
The molar volume depends heavily on the temperature and pressure of the environment; and, a slight variation can change the value of molar volume in all context. To calculate molar volume using the ideal gas law, the equation is PV = nRT.
P is the absolute pressure of the gas. V is the volume of the gas; and, n is the amount of gas in moles. R is the universal gas constant: 0.08206. T is the absolute temperature of the gas. Using this equation, it is easy to calculate the value for molar volume. With standard values for P and T, and an R of 0.08206, the molar volume of one mole of gas is 22.4 L.
The equation is P(1.00 atm) * V = n (1.00 mol) * R (0.08206 L atm/mol/K) * T (273 Kelvin). Using a simple math calculation, multiply 1 * .08206 * 273; and, it results in 22.40238. Then it must be divided by P or 1, to get V, or 22.40238 L, which in its most basic form is 22.4 L.