The metallic lustre of metals is due to :

Options

A. Its high density
B. Its high polishing
C. Its chemical inertness
D. Presence of free electrons

Answer

To solve the question regarding the metallic luster of metals, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Metallic Luster**:
- Metallic luster refers to the shiny appearance of metals when light is reflected off their surfaces.

2. **Role of Electrons in Metals**:
- Metals have a unique structure where some of their electrons are not bound to any particular atom. These are known as "free electrons" or "mobile electrons."

3. **Interaction with Light**:
- When light strikes the surface of a metal, these free electrons can absorb the light energy and then re-emit it. This process is known as reflection.

4. **Reflection of Light**:
- The ability of these free electrons to reflect light is what gives metals their shiny appearance. The more mobile electrons present, the shinier the metal will appear.

5. **Conclusion**:
- Therefore, the metallic luster of metals is primarily due to the presence of free electrons that reflect light effectively.

### Final Answer:
The metallic luster of metals is due to the presence of free electrons.

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