So how many stars are there in the Universe? It is easy to ask this question, but difficult for scientists to give a fair answer! Stars are not scattered randomly through space, they are gathered together into vast groups known as galaxies. The Sun belongs to a galaxy called the Milky Way.
Reverse osmosis. Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules, and larger particles from drinking water.
Reverse Osmosis Definition. Reverse osmosis or RO is a filtration method that is used to remove ions and molecules from a solution by applying pressure to the solution on one side of a semipermeable or selective membrane. Large molecules (solute) can't cross the membrane, so they remain on one side. Water (solvent) can cross the membrane.