The substance that does not have sharp ,melting point is

Options

A. KCl
B. Glass
C. Ice
D. Diamond

Explanation

To determine which substance does not have a sharp melting point, we need to analyze the properties of the given substances: KCl, glass, ice, and diamond.

### Step-by-Step Solution:

1. **Understanding Melting Points**:
- A sharp melting point is characteristic of crystalline solids, where the particles are arranged in a well-defined, orderly structure. When heated, these solids melt at a specific temperature.

2. **Identifying the Types of Solids**:
- **KCl (Potassium Chloride)**: This is an ionic compound and forms a crystalline solid. It has a sharp melting point due to its orderly arrangement of ions.
- **Ice (Solid Water)**: Ice is also a crystalline solid, composed of water molecules arranged in a specific structure. It has a sharp melting point at 0°C.
- **Diamond**: Diamond is a form of carbon that is a crystalline solid with a very high melting point. It also has a sharp melting point due to its orderly arrangement of carbon atoms.
- **Glass**: Glass is an amorphous solid, meaning it lacks a long-range order in its structure. As a result, it does not have a sharp melting point; instead, it softens over a range of temperatures.

3. **Conclusion**:
- Among the substances listed, glass is the only one that does not have a sharp melting point due to its amorphous nature.

### Final Answer:
The substance that does not have a sharp melting point is **glass**.

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