Interstital hydrides are formed by

Options

A. s-block metals
B. p-block metals
C. d-block metals
D. All of these

Answer

To determine what forms interstitial hydrides, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Hydrides**:
- A hydride is a compound formed when hydrogen bonds with another element. There are different types of hydrides based on the nature of the bond.

2. **Types of Hydrides**:
- There are three main types of hydrides:
- **Ionic Hydrides**: Formed with alkali and alkaline earth metals (S-block elements).
- **Covalent Hydrides**: Formed with nonmetals (P-block elements).
- **Interstitial Hydrides**: Formed with transition metals (D-block elements).

3. **Focus on Interstitial Hydrides**:
- Interstitial hydrides are specifically formed by transition metals. These metals have the ability to accommodate hydrogen atoms in the interstitial spaces of their metallic lattice structure.

4. **Formation Mechanism**:
- In interstitial hydrides, hydrogen atoms occupy the interstitial sites within the crystal lattice of the metal. This is characteristic of D-block elements, which have the appropriate lattice structure to allow hydrogen atoms to fit into the gaps.

5. **Conclusion**:
- Therefore, interstitial hydrides are primarily formed by D-block elements (transition metals).

### Final Answer:
**Interstitial hydrides are formed by D-block elements (transition metals).**

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