Osmosis is the passage of a solvent through a semipermeable membrane into a solution. The pressure that halts the osmosis process is known as osmotic pressure. Osmotic pressure is a collective attribute of a material since its value is determined by the solute's concentration rather than its chemical composition. Osmosis is the naturally occurring net movement or diffusion of solvent molecules across a selectively permeable membrane from an area of high water potential to a region of low water potential in a manner that tends to balance the solute concentrations on the two sides.