How many colloidal systems exist in nature in which liquid a dispersed phase?

Answer

To determine how many colloidal systems exist in nature where the dispersed phase is liquid, we can analyze the types of colloids based on the nature of the dispersion medium.

### Step-by-Step Solution:

1. **Identify the Dispersed Phase**:
- The question specifies that the dispersed phase is liquid.

2. **Identify Possible Dispersion Media**:
- The dispersion medium can be solid, liquid, or gas.

3. **Classify Colloidal Systems**:
- Based on the combination of the dispersed phase (liquid) and the different dispersion media, we can classify the colloidal systems:
- **Liquid dispersed in solid**: This type of colloid is known as a **gel**.
- **Example**: Cheese (where liquid is dispersed in a solid matrix).
- **Liquid dispersed in liquid**: This type of colloid is known as an **emulsion**.
- **Example**: Milk (where fat droplets are dispersed in water).
- **Liquid dispersed in gas**: This type of colloid is known as an **aerosol**.
- **Example**: Mist or fog (where tiny water droplets are dispersed in air).

4. **Count the Types**:
- From the classifications above, we can see that there are three types of colloidal systems where the dispersed phase is liquid:
1. Gel (liquid in solid)
2. Emulsion (liquid in liquid)
3. Aerosol (liquid in gas)

5. **Conclusion**:
- Therefore, the total number of colloidal systems in nature where the dispersed phase is liquid is **three**.

### Final Answer:
**Three colloidal systems exist in nature where the dispersed phase is liquid.**

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