Why are semipermeable membranes used in reverse osmosis?

Semipermeable membranes are fundamental to the process of reverse osmosis because they serve to selectively allow certain molecules to pass through while blocking others. In the context of reverse osmosis, the primary function of these membranes is to filter out impurities, contaminants, and unwanted solutes from water, allowing only water molecules to pass through.

The toughness and resilience of semipermeable membranes are crucial as they must withstand high pressures during the reverse osmosis process. This pressure is necessary to reverse the natural osmotic flow, pushing water from a region of higher solute concentration through the membrane into a region of lower solute concentration. The durability of the membrane ensures it can function effectively over time without degrading or allowing contaminants to leak through.

Other options provided do not accurately represent the primary function or benefit of the semipermeable membranes in reverse osmosis. For example, while visible particles may be filtered out by other types of water treatment techniques, the specific purpose of semipermeable membranes is to address dissolved solids rather than visible particles. Affordability is not a characteristic that specifically defines the purpose of these membranes in the filtration process. Additionally, while water quality can influence taste, enhancing water taste is not the direct function of semipermeable membranes