If you have 1 mole of N2 (or any other gas for that matter) under STP conditions it will occupy a volume of 22.4 L. This is known as the “standard molar volume”. So, if you know the number of moles of gas that you have, you can use a simple ratio (1 mole : 22.4 L) to determine the volume of the gas
The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
So, if you have 1 mole of the N2 gas under STP conditions, it means that this gas will occupy a volume of 22.4 L.
