Which of the following is/are pseudo solid ?

Options

A. KCl
B. `BaCl_2. 2H_2O`
C. Rubber
D. Coke

Answer

To determine which of the given substances are pseudo solids, we first need to understand what pseudo solids are. Pseudo solids are materials that, while classified as solids, exhibit a tendency to flow under certain conditions. This characteristic is often associated with amorphous solids.

**Step-by-Step Solution:**

1. **Define Pseudo Solids:**
- Pseudo solids are solids that have a slight tendency to flow, despite being in a solid state. They are often amorphous in nature.

2. **Analyze Each Substance:**
- **KCl (Potassium Chloride):**
- KCl is a crystalline solid. Crystalline solids have a definite structure and do not flow.
- **Conclusion:** KCl is not a pseudo solid.

- **BaCl2·2H2O (Barium Chloride Dihydrate):**
- BaCl2·2H2O is also a crystalline solid. Like KCl, it has a definite arrangement of ions and does not flow.
- **Conclusion:** BaCl2·2H2O is not a pseudo solid.

- **Rubber:**
- Rubber is classified as an amorphous solid. Amorphous solids lack a long-range order and can exhibit flow characteristics under stress.
- **Conclusion:** Rubber is a pseudo solid.

- **Coke:**
- Coke is primarily a crystalline solid made from carbon. It has a definite structure and does not flow.
- **Conclusion:** Coke is not a pseudo solid.

3. **Final Conclusion:**
- The only substance from the list that qualifies as a pseudo solid is rubber.

**Answer: Rubber is the only pseudo solid among the given options.**

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