Following is an amorphous allotrope of carbon.

Options

A. graphite
B. charcoal
C. diamond
D. fullerene

Answer

**Step-by-Step Text Solution:**

1. **Understanding Amorphous Allotropes**:
- Amorphous substances lack a definite crystalline structure. This means they do not have a specific arrangement of atoms or a fixed shape.

2. **Defining Allotropes**:
- Allotropes are different physical forms of the same element. For carbon, this means it can exist in various forms with different structures but with the same chemical properties.

3. **Identifying the Allotropes of Carbon**:
- The common allotropes of carbon include graphite, diamond, fullerene, and charcoal.

4. **Analyzing Each Option**:
- **Graphite**: Has a layered structure with a definite arrangement of carbon atoms, making it a crystalline allotrope.
- **Diamond**: Has a tetrahedral structure where each carbon atom is bonded to four others, also making it crystalline.
- **Fullerene (C60)**: Has a specific structure resembling a soccer ball, consisting of pentagonal and hexagonal arrangements, thus it is crystalline.
- **Charcoal**: Lacks a defined structure and does not have a specific arrangement of carbon atoms, making it an amorphous allotrope.

5. **Conclusion**:
- Among the options provided, the only amorphous allotrope of carbon is **charcoal**.

**Final Answer**: Charcoal is the amorphous allotrope of carbon.

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