Colloids can be prepared by

Options

A. Tyndall effect
B. Electrophoresis
C. Dialysis
D. Peptization

Answer

**Step-by-Step Solution:**

1. **Understanding Colloids:**
- Colloids are mixtures where one substance is dispersed evenly throughout another. They consist of tiny particles that do not settle out and can be solid, liquid, or gas.

2. **Identifying Preparation Methods:**
- To determine how colloids can be prepared, we need to look at the methods typically used in colloid formation.

3. **Analyzing the Given Options:**
- The question mentions several processes: Tyndall effect, electrophoresis, peptization, and dialysis.
- Tyndall effect and electrophoresis are properties of colloids, not methods of preparation.
- Peptization is a method used to prepare colloids from precipitates.
- Dialysis is primarily used for the purification of colloids, not their preparation.

4. **Conclusion:**
- The correct method for preparing colloids from the options provided is **peptization**. This involves converting a precipitate into a colloidal solution by adding a suitable peptizing agent.

**Final Answer:**
Colloids can be prepared by **peptization**.

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