For water, 1 mole = 18 g= 22.4 liter. But practically, how 22.4 liter is equal to 18 g?

  • 1
    $\begingroup$ 22.4 liters of liquid water does not weigh 18 g. Pay attention to the phase. $\endgroup$ – It's Over Oct 23 '16 at 14:45

For water, 1 gram is approximately 1 mL.

22.4 L/mol is the molar volume of an ideal gas at STP.

Since water is not a gas at STP, you can't apply that.

If you had one mole substance that is a gas at STP (hydrogen, nitrogen, carbon dioxide, etc.) you could say that they occupy a volume of approximately 22.4 L.

  • $\begingroup$ 22.4 L/mol is for the "old" STP. The current definition of STP is 0 C and 100 kPa which has a volume of 22.7 L/mol. $\endgroup$ – MaxW Oct 23 '16 at 17:53
  • $\begingroup$ Water can be a gas if it's water vapor. 22.4 L is the volume of 18 g of water vapor at 1 atm and 0 C. $\endgroup$ – Chet Miller Oct 23 '16 at 18:08
  • $\begingroup$ Water can't exist in the gaseous state at these conditions. $\endgroup$ – Vlad Oct 23 '16 at 19:40

Not the answer you're looking for? Browse other questions tagged or ask your own question.