A difference between diffusion and osmosis is

Options

A. A semi-permeable membrane is required for osmosis while diffusion requires no semi-permeable membrane.
B. In osmosis movement of molecules is only in one direction whereas in diffusion movement is on both sides.
C. In osmosis only the solvent moves while in diffusion both solute and solvent move.
D. None of these

Answer

**Step-by-Step Text Solution:**

1. **Definition of Diffusion**:
- Diffusion is the process by which molecules spread from an area of high concentration to an area of low concentration until they are evenly distributed. This process occurs in gases, liquids, and solids.

2. **Definition of Osmosis**:
- Osmosis is a specific type of diffusion that involves the movement of water molecules through a semi-permeable membrane. It occurs when there is a difference in solute concentration on either side of the membrane.

3. **Requirement of Membrane**:
- One of the key differences is that osmosis requires a semi-permeable membrane, which allows only certain molecules (like water) to pass through, while diffusion does not require any membrane.

4. **Direction of Movement**:
- In osmosis, water moves towards the area of higher solute concentration, whereas in diffusion, the movement of molecules is from high concentration to low concentration regardless of the type of molecules.

5. **Types of Molecules Involved**:
- Osmosis specifically involves water molecules, while diffusion can involve any type of molecule, including gases and solutes.

6. **Conclusion**:
- In summary, the main difference between diffusion and osmosis is the requirement of a semi-permeable membrane for osmosis, whereas diffusion occurs without any membrane.

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