Peptization is a process

Options

A. of precipitation of colloidal particles
B. of purification of colloids
C. of dispersing precipitates into colloidal solutions
D. in which colloidal particles moves in an electric field.

Answer

**Step-by-Step Solution:**

1. **Understanding Peptization:**
- Peptization is a process that involves the conversion of a precipitate into a colloidal solution. This is achieved by adding a suitable electrolyte, known as a peptizing agent.

2. **Identifying the Role of Electrolytes:**
- When an electrolyte is added to a freshly precipitated substance, it helps to disperse the particles into a colloidal form. This is because the electrolyte neutralizes the charges on the precipitate particles, allowing them to come closer together and form a stable colloidal solution.

3. **Example of Peptization:**
- A common example is the addition of ferric chloride (an electrolyte) to freshly precipitated ferric hydroxide. The ferric chloride helps to disperse the ferric hydroxide into a reddish-brown colloidal solution.

4. **Evaluating the Options:**
- Now, let's analyze the given options:
- **Option 1:** Precipitation of colloidal particles - Incorrect, as peptization is about dispersing, not precipitating.
- **Option 2:** Purification of colloids - Incorrect, as this does not describe peptization.
- **Option 3:** Dispersing precipitates into colloidal solution - Correct, as this is the definition of peptization.
- **Option 4:** Colloidal particles moving in an electric field - Incorrect, as this describes electrophoresis, not peptization.

5. **Conclusion:**
- The correct answer is **Option 3: Dispersing precipitates into colloidal solution**.

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