Which process involves solvent molecules moving through a semipermeable membrane?

The process where solvent molecules move through a semipermeable membrane is called osmosis. In osmosis, water molecules travel from a region of lower solute concentration to a region of higher solute concentration, aiming to achieve equilibrium on both sides of the membrane. The semipermeable nature of the membrane allows only solvent molecules (like water) to pass through while preventing solute particles (such as salts or sugars) from crossing. This is crucial in biological systems, as it helps maintain cell turgor and regulates various physiological processes.

The other processes listed differ significantly in their mechanisms. Evaporation involves the transition of liquid to gas, which does not involve a membrane. Diffusion refers to the movement of solute molecules from an area of higher concentration to one of lower concentration and can occur in any medium, not specifically involving a membrane. Filtration is the process of separating solids from liquids or gases using a filter, which is not specific to the movement of solvent molecules through a semipermeable membrane but rather relies on physical barriers.