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Questions
Explain the difference between osmosis and diffusion.
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Solution
| Sr. No. | Diffusion | Osmosis |
| 1. | It is the movement of molecules of a substance from a region of higher concentration to a region of lower concentration. | It is the process in which water molecules move through a semi-permeable membrane from a region of higher concentration to a region of lower concentration. |
| 2. | Diffusion involves the free mixing of the solution without a semipermeable membrane. | Osmosis involves the use of a semipermeable membrane. |
| 3. | In diffusion, both solvent and solute molecules move directly into each other. Thus, it is a bilateral process. | In osmosis only solvent molecules move through the semipermeable membrane. The movement of solute particles is checked by the semipermeable membrane. |
| 4. | It is shown by solutions as well as by gases. | It is shown by solutions only. |
| 5. | It can neither be stopped nor reversed. | It can be stopped or reversed by applying external pressure on the solution having a higher concentration. |
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