Take three test tubes and label them as A,B and C. Fill upto two -third with sugar solution, chalk powder in water and milk, respectively. Allow these to stand on test tube stand for some time.
(i) In which of the test tubes will you observe particles settle down?
(ii) Which of the test tubes will look transparent?
(iii) Which of the test tubes will look opaque ?

Explanation

**Step-by-Step Solution:**

1. **Observation of Settling Particles:**
- In test tube A, we have a sugar solution. Sugar dissolves completely in water, so no particles will settle down.
- In test tube B, we have chalk powder mixed with water. Chalk powder does not dissolve in water and will settle down at the bottom after some time.
- In test tube C, we have milk. Milk is a colloid, and while it may appear homogeneous, the particles do not settle down completely.
- **Conclusion:** Particles will settle down in **test tube B** (chalk powder in water).

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