Which is not a property of lyophilic sols .

Options

A. It can be prepared directly by mixing dispersion phase and dispersion medium
B. It is reversible
C. Viscosity of disperged phase same as that of dispersion medium
D. It particles do not carry charge

Answer

To determine which statement is not a property of lyophilic sols, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Lyophilic Sols**:
- Lyophilic sols are colloidal systems where the dispersed phase has a strong affinity for the dispersion medium. This means that the particles of the dispersed phase mix well with the medium.

**Hint**: Recall that "lyophilic" translates to "solvent-loving," indicating a strong interaction with the dispersion medium.

2. **Analyzing the Options**:
- **Option 1**: "Can be prepared directly by mixing dispersion phase and dispersion medium."
- This statement is true. Lyophilic sols can indeed be formed by simply mixing the dispersed phase with the dispersion medium.

**Hint**: Consider how substances like gum or gelatin are made by mixing with water.

- **Option 2**: "The sol can be reconstituted by remixing with the dispersion medium."
- This statement is also true. If the dispersion medium is separated from the dispersed phase, the sol can be reconstituted by adding the dispersion medium back.

**Hint**: Think about how you can dissolve a gel back into a liquid.

- **Option 3**: "Viscosity of disperse phase same as that of dispersion medium."
- This statement is correct. In lyophilic sols, the viscosity of the dispersed phase is typically similar to that of the dispersion medium, which contributes to the stability of the sol.

**Hint**: Remember that viscosity relates to the flow characteristics of the mixture.

- **Option 4**: "Its particles do not carry charge."
- This statement is incorrect. Lyophilic sols do carry charge, which can be positive or negative. The charge on the particles contributes to the stability of the sol by preventing aggregation.

**Hint**: Consider how charge affects the stability of colloidal systems.

3. **Conclusion**:
- The statement that is not a property of lyophilic sols is **Option 4**: "Its particles do not carry charge." This is incorrect because the particles in lyophilic sols do carry charge.

### Final Answer:
**Option 4** is the correct answer as it is not a property of lyophilic sols.