Question:
Which phenomenon is responsible for desalination of sea water?
Which phenomenon is responsible for desalination of sea water?
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In Reverse Osmosis, the solvent moves from a region of high solute concentration to low solute concentration, which is opposite to natural osmosis.
Updated On: Jul 22, 2026
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Solution and Explanation
Concept:
Desalination is the process of removing salts from saline water. It relies on:
• Semi-permeable membrane (SPM): A membrane that allows only solvent molecules to pass.
• External Pressure: Force applied to overcome natural osmotic flow.
Step 1: Defining the process.
If a pressure larger than the osmotic pressure is applied to the solution side (sea water), the pure solvent (water) flows out of the solution through the semi-permeable membrane. This is called Reverse Osmosis.
Step 2: Practical setup.
In desalination, sea water is placed on one side of a semi-permeable membrane (often made of cellulose acetate). When high pressure is applied, pure water is pushed through the membrane into the fresh water side, leaving the concentrated salt behind.
• Semi-permeable membrane (SPM): A membrane that allows only solvent molecules to pass.
• External Pressure: Force applied to overcome natural osmotic flow.
Step 1: Defining the process.
If a pressure larger than the osmotic pressure is applied to the solution side (sea water), the pure solvent (water) flows out of the solution through the semi-permeable membrane. This is called Reverse Osmosis.
Step 2: Practical setup.
In desalination, sea water is placed on one side of a semi-permeable membrane (often made of cellulose acetate). When high pressure is applied, pure water is pushed through the membrane into the fresh water side, leaving the concentrated salt behind.
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