How are interstitial solids formed ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Interstitial Spaces**: In a crystalline lattice, atoms are arranged in a specific geometric pattern. However, there are small spaces or voids between these atoms known as interstitial spaces.

2. **Formation of Interstitial Solids**: Interstitial solids are formed when these interstitial spaces are occupied by smaller atoms or non-metals. These smaller atoms can fit into the voids without disrupting the overall structure of the crystal.

3. **Examples of Interstitial Solids**: A common example of interstitial solids is steel, which is primarily made of iron. In the crystalline structure of iron, there are interstitial spaces that can be filled by smaller non-metal atoms such as carbon, hydrogen, boron, or nitrogen.

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