The Band Theory

In an insulating material, _______.

• the valence band is filled and the conduction

  band is empty

• the valence band is empty and the

  conduction band is filled

• both the valence band and conduction band

  are empty

• both the valence band and conduction band

  are filled

• both the valence band and conduction band

  are partially filled

A material with 5 eV forbidden gap energy is:

• conductor

• An insulator

• A semiconductor

• An isolated molecule

• An isolated atom

A material with a relatively large gap between its

valance band and conduction band would be

expected to be ______.

• a good conductor

• easily melted

• a poor conductor

• in the liquid state

• crystalline material

Tags

NGSS.HS-PS1-3

According to the band theory of solids, why is lead

a good conductor?

• There is a wide energy gap between the

  valance band and conduction band of lead

• The valance band of lead is empty and the

  conduction band is filled

• The valance band and the conduction

  band of lead is half filled.

• A great deal of energy is needed to move

  valence electrons of lead to the conduction

  band

• The conduction band of lead overlaps the

  valance band

Tags

NGSS.HS-PS1-3

What is the approximate energy gap between the

valance band and conduction band of insulators?

• 0 eV

• 1 eV

• 5 eV

• 10 eV

• 100 eV

Which of the following is not a semiconductor?

• Silicon

• Gallium

• Germanium

• Aluminum

• Antimony

If a material contains overlapping conduction and

valence bands, both of which are partially

filled, then ____.

• no potential difference is required to

  induce a current in the material

• the acceleration of electrons will require a

  relatively large input of radiation

• the conductance of the material will be

  directly related to its temperature

• a small electric field will make electrons

  move from one atom to another

• the acceleration of electrons will require

  doping of the material

A material that conducts electricity well tends to

have ______.

• no valance electrons

• partially filled bands

• completely filled bands

• conduction and valance bands that are far

  apart

• a full valence band and an empty

  conduction band

Tags

NGSS.HS-PS2-5

________ is an insulator.

• Copper

• Silicon

• Gold

• Table salt

• Germanium

In a conductor, conductivity increases as ______.

• temperature decreases

• the applied electrical field decreases

• resistance increases

• more electrons move into the valence

  band