Along with some solute molecules shown in green. The two sides are separated by a semipermeable membrane that only allows water to move across. Now, since pure water has an asthmatic pressure and an osmotic potential of zero, but the right side has a more negative osmotic potential, so it's smaller osmotic potential. Water will naturally flow from the left side to the right side, down the osmotic potential gradient. Now, we can rephrase this. We can say that water moves from a low solute concentration, the left side, to a higher solid concentration, the right side.