Low melting point is expected for a solid :

Options

A. Ionic solid
B. Metallic solid
C. Molecular solid
D. Covalent solid

Explanation

To determine why a solid might have a low melting point, we can analyze the types of solids and the forces that hold their particles together. Here’s a step-by-step breakdown of the reasoning:

### Step 1: Understand the Types of Solids
There are four main types of solids:
1. **Ionic Solids**
2. **Metallic Solids**
3. **Covalent Network Solids**
4. **Molecular Solids**

### Step 2: Identify the Forces of Attraction
Each type of solid is held together by different types of forces:
- **Ionic Solids**: Held together by strong electrostatic forces of attraction between oppositely charged ions.
- **Metallic Solids**: Held together by metallic bonds, which involve a sea of delocalized electrons.
- **Covalent Network Solids**: Atoms are bonded by covalent bonds in a giant network, which are strong but can vary in strength.
- **Molecular Solids**: Held together by weaker intermolecular forces such as dipole-dipole interactions, hydrogen bonds, and London dispersion forces.

### Step 3: Compare the Strength of Forces
The strength of the forces can be ordered from strongest to weakest:
1. **Ionic Forces** (strongest)
2. **Metallic Forces**
3. **Covalent Forces**
4. **London Forces** (weakest)

### Step 4: Relate Forces to Melting Points
The melting point of a solid is directly related to the strength of the forces holding its particles together. Stronger forces result in higher melting points, while weaker forces lead to lower melting points.

### Step 5: Conclusion
Since molecular solids are held together by the weakest forces (London dispersion forces), they are expected to have the lowest melting points among the types of solids. Thus, a solid with a low melting point is likely a molecular solid.

### Final Answer
A solid with a low melting point is expected to be a **molecular solid** due to the weak intermolecular forces (London forces) that hold its particles together.

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