Osmosis — EdVibe Simulation

How to use: Two solutions are separated by a partially permeable membrane. The membrane lets water through, but not solute. Change the solute amounts with the sliders. Watch blue water molecules cross the membrane from the dilute side (fewer solutes) to the concentrated side (more solutes). The graph shows how the water splits between the two sides over time. Try setting both sides to the same solute — does anything happen?

Notice: water always moves toward the more concentrated solution — the side with more solute. This is osmosis. In cells, this is how roots take up water from soil, and why a plant wilts if you water it with salty water. If both sides have the same concentration, water moves both ways at the same rate — no net change.