Transition metals, when they form interstitial compounds, the non-metals (H,B,C,N) are accommodated in:

Options

A. voids or holes in cubic-packed structure
B. tetrahedral voids
C. octahedral voids
D. all of these

Answer

To solve the question regarding the accommodation of non-metals (H, B, C, N) in interstitial compounds formed by transition metals, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Interstitial Compounds**:
- Interstitial compounds are formed when small non-metal atoms (like hydrogen, boron, carbon, and nitrogen) occupy the vacant spaces (interstitial sites) in the lattice structure of transition metals.

2. **Identify the Structure of Transition Metals**:
- Transition metals typically crystallize in close-packed structures such as Hexagonal Close-Packed (HCP) or Face-Centered Cubic (FCC) structures.

3. **Determine the Types of Voids**:
- In these close-packed structures, there are different types of voids where smaller atoms can fit:
- **Tetrahedral Voids**: These are formed when four atoms surround a central void.
- **Octahedral Voids**: These are formed when six atoms surround a central void.

4. **Analyze the Options Given**:
- The question provides options: voids or holes in cubic packed structure, tetrahedral voids, octahedral voids, and all of these.
- Since interstitial compounds can accommodate non-metals in any of these voids, we need to consider all possibilities.

5. **Conclusion**:
- Since non-metals can occupy tetrahedral voids, octahedral voids, and any other voids in the cubic structure, the correct answer is that they can be accommodated in **all of these**.

### Final Answer:
The non-metals (H, B, C, N) are accommodated in **all of these**: voids or holes in cubic packed structure, tetrahedral voids, and octahedral voids.

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