When a semi permeable membrane (a material with extremely small holes in it so that it allows only solvent molecules to pass through it) separates a solvent from a solution, solvent molecules tend to pass from the solvent side into the solution.For More Chemistry Formulas just check out main page of Physics Wallah.
Also, if the solutions of different concentrations are separated by semi permeable membrane, the solvent molecule pass from dilute solution into the more concentrated solution. This movement of solvent molecules through a semi permeable membrane is called as osmosis.
Q1.Calculate the osmotic pressure in pascals exerted by a solution prepared by dissolving 1.0 g of polymer of molar mass 185,000 in 450 mL of water at 37°C.
Ans. 31 Pa (approx)