CHAPTER 21

Which of the following is a correct comparison of metals and semi-conductors? Select one:

Metals' resistance increases when temperature increases while a semi-conductors resistance decreases.

When we increase the temperature of the material

the conductivity of metals decreases whereas that of semi-conductors increases

Partially filled bands lead to materials that tend to

be opaque, be malleable, conduct heat well, conduct electricity well

Why are metals opaque? Select one:

because metals have empty, overlapping orbitals for their electrons

Metals have higher ionization energies than non-metals do. Select one:

false

Locate the elements palladium (Pd, atomic #46) and nickel (Ni, atomic #28) on the periodic table. If Pd is combined with Ni, which of the following characteristics will the product show at room temperature? Select one:

Shiny, malleable solid.

When you compare the band gap for a red and a blue LED, what is true? Select one:

The red LED has the smallest band gap.

Which of the following is NOT why alloys are useful to us today? Alloys Select one:

have a higher conductivity rate.