Solids having highest energy level partially filled with electrons are

Options

A. An insulator
B. A conductor
C. A semiconductor
D. None of these

Answer

To solve the question "Solids having highest energy level partially filled with electrons are," we need to analyze the characteristics of different types of solids based on their electronic structure. Here’s a step-by-step breakdown:

### Step 1: Understand the Types of Solids
There are three main types of solids based on their electrical conductivity:
1. **Conductors**: Materials that allow the flow of electric current easily.
2. **Insulators**: Materials that do not allow the flow of electric current.
3. **Semiconductors**: Materials that have conductivity between that of conductors and insulators.

### Step 2: Analyze the Energy Bands
In solid-state physics, the energy levels of electrons in a solid are grouped into bands:
- **Valence Band**: The energy band that is filled with electrons.
- **Conduction Band**: The energy band that is partially filled or empty and allows electrons to move freely, contributing to electrical conductivity.

### Step 3: Identify the Characteristics of Each Type
- **Conductors**: In conductors, the highest energy band (conduction band) is partially filled with electrons. This allows for easy movement of electrons, resulting in high conductivity.
- **Insulators**: In insulators, the conduction band is completely empty, and the valence band is completely filled. This prevents the flow of electrons and thus does not conduct electricity.
- **Semiconductors**: Semiconductors have a conduction band that is partially filled or can be made to conduct under certain conditions (like doping or applying heat).

### Step 4: Determine the Correct Answer
Given the question, we need to identify which type of solid has its highest energy level partially filled with electrons. The only type of solid that fits this description is a **conductor**.

### Conclusion
Therefore, the correct answer to the question is:
**Option 2: Conductor**

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