What is reverse osmosis?

Explanation

(i) The pure water moves through the semipermeable membrane to the NaCl solution due to osmosis.
(ii) This process can be reversed by applyingh pressure greater than the osmotic pressure to the solution side. Now the pure water moves from the solution side to the solvent side and this process is called reverse osmosis.
(iii) Reverse osmosis can be defined as a process in which a solvent passes through a semipermeable membrane in the opposite direaction of osmosis, when subjected to a hydrostatic pressure greater than the osmotic pressure.