Which process involves using pressure to push water through a filter?

The correct process that involves using pressure to push water through a filter is reverse osmosis. In this process, water is forced through a semi-permeable membrane which allows only water molecules to pass while blocking contaminants and dissolved solids. The application of pressure is crucial in overcoming osmotic pressure and enables the separation of impurities from the water, resulting in purified water on one side of the membrane and a concentrated solution of contaminants on the other side.

This method is widely used in water purification and desalination because it effectively removes a variety of impurities, making it essential for applications requiring high-quality water. The significance of pressure in reverse osmosis is what differentiates it from other processes like filtration, demineralization, and softening, which do not rely on high pressure to achieve their results.