Which of the following processes is used for the separation of colloidal particles from particles of molecular dimensions ?

Options

A. Dialysis
B. Coagulation
C. Plasmolysis
D. None of these

Answer

To solve the question regarding the separation of colloidal particles from particles of molecular dimensions, we will analyze the given options step by step.

### Step 1: Understanding the Terms
- **Colloidal Particles**: These are larger particles that are suspended in a medium and cannot be separated by simple filtration.
- **Molecular Dimensions**: These refer to very small particles or molecules that can easily pass through membranes.

### Step 2: Analyzing the Options
1. **Dialysis**: This process involves the separation of colloidal particles from smaller particles (like ions or small molecules) using a semi-permeable membrane. The membrane allows smaller particles to pass through while retaining larger colloidal particles.

2. **Coagulation**: This is a process where colloidal particles aggregate to form larger particles, which can then settle out of the solution. It does not separate colloidal particles from smaller particles.

3. **Plasmolysis**: This is a biological process that occurs in plant cells when they lose water in a hypertonic solution. It is not related to the separation of colloidal particles.

4. **None of these**: This option suggests that none of the processes listed are suitable for the separation in question.

### Step 3: Conclusion
Based on the analysis, the only process that effectively separates colloidal particles from particles of molecular dimensions is **Dialysis**.

Thus, the answer to the question is **Dialysis (Option A)**.

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