Molar Volume:
The volume occupied by one mole of an ideal gas at standard temperature and pressure (STP) is called molar volume. Its value is 22.414dm3 0.022414 cm3.
Example:
2.016g of H2 = 1mole of H2=6.022×1023 molecules of H2 = 22.414dm3 of H2 at S.T.P.
16g of CH4 = 1mole of CH4=6.022×1023 molecules of CH4 = 22.414dm3 of CH4 at S.T.P.
It is very interesting to know from the above data that 22.414dm3 of each gas has a different mass but the same number of molecules.
Reason:
The reason is that the masses and the sizes of the molecules do not affect the volumes. Normally, it is known that in the gaseous state the distance between molecules is 300 times greater than their diameters.