What is the forbidden energy gap in a pure conductor?

Question:

What is the forbidden energy gap in a pure conductor?

1. 1.1 eV
2. 0.72 eV
3. 3.0 eV
4. 0 eV

Answer:
The correct option is (4)
What is the forbidden energy gap in a pure conductor? Answer: The forbidden energy gap in a pure conductor is 0 eV.

Explanation:

In a pure conductor, the forbidden energy gap concept is not applicable because pure conductors have their valence band and conduction band overlapping, unlike semiconductors or insulators.

To understand this, let’s break down the concept:

1. Energy Bands: In solid-state physics, materials are often described in terms of energy bands. These bands represent ranges of energy levels that electrons in the material can occupy. The two main bands relevant to this discussion are the valence band and the conduction band.
2. Valence Band: This band represents the range of energy levels occupied by valence electrons, which are the electrons involved in bonding between atoms in a material.
3. Conduction Band: This band represents the range of energy levels that electrons can move into and become free to conduct electricity. In insulators and semiconductors, there’s a distinct energy gap between the valence band and the conduction band. Electrons in the valence band cannot easily move to the conduction band because of this gap.
4. Forbidden Energy Gap: In insulators and semiconductors, this is the energy range between the valence band and the conduction band where no electrons are normally found. This gap needs to be overcome for electrons to move from the valence band to the conduction band, which typically requires external energy such as heat or light.

However, in pure conductors like most metals, the situation is different:

• No Forbidden Gap: In pure conductors, the valence band and the conduction band overlap. This means that there’s no distinct energy gap between them. Electrons in the valence band can easily move into the conduction band without needing external energy because there’s no energy barrier to overcome.
• High Conductivity: This overlap between the bands contributes to the high electrical conductivity of metals. Electrons can move freely through the material in response to an electric field because there’s no energy barrier to impede their movement.

So, in summary, the concept of a forbidden energy gap is not relevant to pure conductors because their valence and conduction bands overlap, allowing electrons to move freely and conduct electricity with ease.

Q1. The Forbidden Energy Gap for Germanium is:
Q2. An n-type Semiconductor is_________