Which of the following properties distinguish a material as conductor, insulator and semiconductor?

Materials are categorized as conductors, insulators, and semiconductors based on their electrical conductivity and the energy gap between their valence and conduction bands. Let’s explore the distinguishing properties of each:

### Conductors

1. Electrical Conductivity: High electrical conductivity.
2. Resistance: Low resistance to the flow of current.
3. Energy Bands: Overlapping valence and conduction bands, allowing electrons to flow freely even at low energy levels.
4. Temperature Dependence: Their conductivity decreases with an increase in temperature, as the lattice vibrations scatter electrons more at higher temperatures.
5. Examples: Metals like copper, silver, and aluminum.

### Insulators

1. Electrical Conductivity: Very low to almost zero electrical conductivity under normal conditions.
2. Resistance: High resistance to the flow of current.
3. Energy Bands: A large energy gap between the valence and conduction bands, making it difficult for electrons to jump from the valence to the conduction band under normal conditions.
4. Temperature Dependence: Their conductivity can increase with temperature, but it remains significantly low compared to conductors and semiconductors.
5. Examples: Rubber, glass, and plastic.

### Semiconductors

1. Electrical Conductivity: Semiconductor’s conductivity is between that of insulators and conductors. It can be significantly altered by adding impurities (doping) or changing the temperature.

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