Which among the following will show anisotropy ?

Options

A. Glass
B. Barium chloride
C. Wood
D. Paper

Explanation

To determine which among the given options will show anisotropy, we need to understand the concepts of anisotropy and isotropy in the context of solid-state chemistry.

### Step-by-Step Solution:

1. **Define Anisotropy and Isotropy**:
- **Anisotropy** refers to the property of a material where its physical properties vary when measured along different directions. For example, the thermal conductivity or refractive index of a material may differ based on the direction in which it is measured.
- **Isotropy**, on the other hand, is when a material exhibits the same physical properties in all directions.

2. **Identify the Nature of the Materials**:
- The question presents several materials, and we need to identify which of them are crystalline solids:
- **Beryllium Chloride (BeCl2)**: This is a crystalline solid.
- **Glass**: Typically considered an amorphous solid, not crystalline.
- **Wood**: A natural composite material, which is generally anisotropic due to its fibrous structure.
- **Paper**: Also a composite material, which can show anisotropic properties depending on the direction of the fibers.

3. **Analyze the Options**:
- Among the options, Beryllium Chloride is the only crystalline solid. Crystalline solids are known to exhibit anisotropic properties because their internal structure is ordered in a specific arrangement, leading to different properties in different directions.
- Wood and paper can show anisotropic behavior due to their fibrous structure, but they are not classified as crystalline solids.
- Glass is amorphous and typically shows isotropic properties.

4. **Conclusion**:
- The only crystalline solid listed that will show anisotropy is **Beryllium Chloride (BeCl2)**.

### Final Answer:
**Beryllium Chloride (BeCl2) will show anisotropy.**

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