Osmosis vs Reverse Osmosis
The concept of osmosis is a very important one that helps in maintaining water levels inside cells of both plants as well as animals. It refers to the net movement of water from one side of a semi permeable membrane to the other side due to the difference in the concentration of solute on the two sides. This diffusion of water is through a selectively semi permeable membrane that allows passage of water but stops passage of other molecules that are either large or are ions. There is another related concept called reverse osmosis that is made use of in making water pure though osmosis itself is used for purification of water. The difference between osmosis and reverse osmosis can be understood once one has a clear understanding of the process of osmosis.
In the process of osmosis, water flows from the solution that has lower concentration of solute into the solution with higher concentration of solute. In other words, water molecules flow from the solution having higher water concentration to a region of lower water concentration. In plants and animals, cell membranes are like semi permeable membranes that allow free passage of small molecules like oxygen, carbon dioxide, ammonia, glucose, amino acids, water molecules etc but stop passage of larger molecules like starch, proteins etc. In general, if the medium surrounding the cell has lower concentration of water than inside of the cell, there will be net movement of water from the cell into the medium. If it’s higher concentration of water, the cell will receive movement of water inside thus causing the cell to swell The cell loses water through osmosis. If the water concentration is same inside the cell and the medium, there is no net movement of water (water going in is equal to water going out) and hence there is no osmosis.
Osmosis is a natural phenomenon taking place regularly in all living beings. This process is made use of in water purification, and also in many other industrial applications. In water purification process, osmosis helps in water flowing from the side of low solute concentration to the side of high solute concentration (from higher water concentration to lower water concentration). This water flow (or osmosis) can however be stopped by the use of external pressure on the side having higher solute concentration and can even be reversed which is known as reverse osmosis.
The process of reverse osmosis is made use of in water filters, refrigeration, RO water purifiers, brewing of beer, reverse osmosis for ships and boats, in hospitals for sterilization, and in clinical analysis.
Difference Between Osmosis and Reverse Osmosis
• The concept of osmosis is the passage of water molecules from high water concentration side through a semi permeable membrane to a low water concentration side and plays a vital role in biological processes in all plant and animal cells.
• Osmosis is also used for water purification but reverse osmosis which refers to stopping, and eventually reversing the process of osmosis through application of external pressure on the side having higher solute concentration is considered more important in water purification as water becomes absolutely pure through reverse osmosis.