Reverse osmosis (RO) membranes remove dissolved salts by applying pressure greater than the ________ pressure.
- Atmospheric
- Osmotic
- Vapor
- Hydrostatic
Answer: Osmotic
RO forces water through semi-permeable membrane against osmotic gradient, rejecting ions/molecules. Widely used for desalination and water purification. [[CPCB Guidelines, NCERT Chemistry Class 12]]