The size of the colloid particles is :

Options

A. Between 0.00002 and 0.02 mm
B. Less than 0.002 mm
C. 0.5-1.0 mm
D. 0.02-0.2 mm

Answer

**Step-by-Step Solution:**

1. **Understanding Colloidal Particles:**
- Colloidal particles are small solid materials that are suspended in a fluid. This suspension allows them to remain dispersed rather than settling at the bottom.

2. **Size Range of Colloidal Particles:**
- The size of colloidal particles typically ranges from approximately 10 nanometers (nm) to several micrometers (μm). This range is crucial as it defines the characteristics of colloids.

3. **Conversion of Units:**
- To express the size in millimeters, we can convert nanometers and micrometers:
- 10 nm = 10 x 10^-9 meters = 0.00001 mm
- Several micrometers can be approximated to a few micrometers, for example, 1 μm = 1 x 10^-6 meters = 0.001 mm.
- Therefore, colloidal particles are less than 0.2002 mm in size.

4. **Understanding Suspension:**
- The reason colloidal particles remain suspended in a fluid is due to their small size, which allows them to be influenced by thermal motion. This thermal motion keeps them from settling.

5. **Conclusion:**
- Based on the above information, we conclude that the size of colloidal particles is less than 0.2002 mm.

**Final Answer:**
The size of colloidal particles is less than 0.2002 mm.

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