Molar Volume
The volume occupied by one mole of a substance under stated conditions of temperature and pressure.
Formula / equation
V_m = V / n = RT / p
Unit
L/mol
In depth
For an ideal gas the molar volume is independent of identity, since equal numbers of particles occupy equal volumes — Avogadro's law. It is 22.414 L/mol at 0 °C and 1 atm, or 24.79 L/mol at 25 °C and 100 kPa. For liquids and solids molar volume varies widely with packing efficiency.
Examples in the real world
One mole of any ideal gas fills 22.4 L at STP; liquid water's molar volume is only 18 mL/mol.