Which type of solids will have the highest melting point ?

Options

A. Ionic crystals
B. Network covalent solid
C. Molecular solids
D. Metallic crystals

Answer

To determine which type of solid has the highest melting point, we can analyze the different types of solids and their characteristics:

### Step 1: Understand the Types of Solids
1. **Ionic Solids**: These are formed by ionic bonds between positively and negatively charged ions. They generally have high melting points due to the strong electrostatic forces between the ions.

2. **Covalent Network Solids**: These solids consist of atoms connected by covalent bonds in a continuous network. They have very high melting points because breaking these bonds requires a significant amount of energy.

3. **Molecular Solids**: These consist of molecules held together by intermolecular forces such as Van der Waals forces, dipole-dipole interactions, or hydrogen bonds. They typically have lower melting points compared to ionic and covalent network solids.

4. **Metallic Solids**: These are composed of metal atoms that are held together by metallic bonds. Their melting points can vary widely, but they are generally lower than those of ionic and covalent network solids.

### Step 2: Compare the Melting Points
- **Ionic Solids**: High melting point (but lower than covalent network solids).
- **Covalent Network Solids**: Very high melting point (the highest among the types listed).
- **Molecular Solids**: Lower melting point (due to weaker intermolecular forces).
- **Metallic Solids**: Varies, but generally lower than ionic and covalent network solids.

### Step 3: Conclusion
Based on the comparison, **covalent network solids** have the highest melting points due to the strong covalent bonds throughout the structure.

### Final Answer
The type of solid that will have the highest melting point is **network covalent solid**.

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