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The energy gaps (E(g)) between valence b...

The energy gaps `(E_(g))` between valence band and conduction band for diamond, silicon and germanium are in the order

A

`E_(g)` (diamond) `gtE_(g)` (silicon)`gtE_(g)` (germanium)

B

`E_(g)` (daimond) `ltE_(g)` (silicon) `ltE_(g)` (germanium)

C

`E_(g)` (diamond) `=E_(g)` (silicon) `=E_(g)` (germanium)

D

`E_(g)` (diamond `gtE_(g)` (germanium) `gtE_(g)` (silicon).

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To determine the order of the energy gaps (E_g) between the valence band and conduction band for diamond, silicon, and germanium, we can follow these steps: ### Step 1: Identify the materials and their properties - **Diamond**: An allotrope of carbon, known for its strong covalent bonding and high energy gap. - **Silicon**: A semiconductor with a moderate energy gap. - **Germanium**: Another semiconductor with a smaller energy gap compared to silicon. **Hint**: Remember that the energy gap is related to the type of bonding and the atomic structure of the materials. ### Step 2: Understand the concept of energy gaps - The energy gap (E_g) is the energy difference between the top of the valence band and the bottom of the conduction band. - A larger energy gap typically indicates a material that is an insulator (like diamond), while a smaller energy gap indicates a semiconductor (like silicon and germanium). **Hint**: Consider how the atomic structure influences the energy levels of electrons in these materials. ### Step 3: Compare the energy gaps - **Diamond**: Has the largest energy gap due to its strong covalent bonds and tightly held valence electrons. E_g for diamond is approximately 5.5 eV. - **Silicon**: Has a moderate energy gap, which is about 1.1 eV. It is a semiconductor that can conduct electricity under certain conditions. - **Germanium**: Has the smallest energy gap of about 0.66 eV. It is also a semiconductor but less effective than silicon. **Hint**: Recall that as you move from diamond to germanium, the atomic number increases, and the energy gap decreases. ### Step 4: Establish the order of energy gaps Based on the values discussed: - Diamond (E_g ≈ 5.5 eV) > Silicon (E_g ≈ 1.1 eV) > Germanium (E_g ≈ 0.66 eV) Thus, the order of energy gaps between the valence band and conduction band for diamond, silicon, and germanium is: **Diamond > Silicon > Germanium** **Final Answer**: The energy gaps (E_g) are in the order: Diamond > Silicon > Germanium.
To determine the order of the energy gaps (E_g) between the valence band and conduction band for diamond, silicon, and germanium, we can follow these steps: ### Step 1: Identify the materials and their properties - **Diamond**: An allotrope of carbon, known for its strong covalent bonding and high energy gap. - **Silicon**: A semiconductor with a moderate energy gap. - **Germanium**: Another semiconductor with a smaller energy gap compared to silicon. **Hint**: Remember that the energy gap is related to the type of bonding and the atomic structure of the materials. ...
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Knowledge Check

  • Assertion : The electrons in the conduction band have higher energy than those in the valence band of a semiconductor Reason : The conduction band lies above the energy gap and valence band lies below the energy gap.

    A
    If both assertion and reason are true and reason is the correct explanation of assertion.
    B
    If both assertion and reason are true not but reason is not the correct explanation of assertion.
    C
    If assertion is true but reason is false
    D
    If both assertion and reason are false.

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