Chapter 21 Practice Test

Question 1

Which of the following is NOT a property of a metal?

Answer 1

Solid at standard temperature

Question 2

Which of the following is not a refining method?

Answer 2

Distilling

Question 3

Which of the following represents the reduction step in processing?

Answer 3

ZnO + C → Zn + CO

Question 4

Which of the following is not an alloy?

Answer 4

iron

Question 5

Which of the following is a property of a metal?

Answer 5

conduct electricity

Question 6

Which of the following shows the electron configuration for di-lithium in a gas state?

Answer 6

2s ____↑↓_____

Question 7

Which of the following electron configuration would be an electrical conductor?

Answer 7

[Cu] 4s13d10

Question 8

Which of the following electron diagrams shows lithium?

Answer 8

2s ____↑_____

Question 9

What type of solid is diamond?

Answer 9

Network

Question 10

Germanium is used in nuclear physics as a radiation detector. The energy gap in germanium is 0.72 eV. Suppose a 600-keV photon passes through a germanium crystal, gradually losing all of its energy by exciting electrons to the conduction band. About how many electrons will be moved to the conduction band?

Answer 10

8.3 × 10^5 electrons

Question 11

Which one of the following has the largest energy gap between the valence band and the conduction band?

Answer 11

An insulator

Question 12

What happens to the conductivity of a semiconductor as the temperature increases?

Answer 12

It increases.

Question 13

Which of the following results in a p-type semiconductor?

Answer 13

Si doped with Al

Question 14

Which of the following mixtures is least likely to have the characteristics of a semiconductor?

Answer 14

ZnO

Question 15

As the temperature of a metal is increased, the conductivity decreases because molecular orbitals are perturbed by the vibrational energy of the atoms. Which of the following describes what happens to the conductivity of semiconductors with increasing temperature?

Answer 15

The conductivity increases but then decreases at even higher temperatures

Question 16

Which of the following results in an n-type semiconductor?

Answer 16

Ge doped with As

Question 17

What is the most common oxidation state for alkali metals?

Answer 17

+1

Question 18

Which of the following elements is an alkali metal?

Answer 18

Lithium, Li

Question 19

Which two alkali metals are essential elements in living organisms?

Answer 19

Sodium and potassium

Question 20

What is the third most common element in seawater?

Answer 20

Magnesium

Question 21

Arrange the steps of the Dow process of magnesium isolation in the correct order:

1. Mg(OH)2 + HCl -> MgCl2 + 2H2O
2. Mg2+ + 2OH- -> Mg(OH)2
3. CaO + H2O -> Ca(OH)2
4. MgCl2(l) -> Mg(s) + Cl2(g)

Answer 21

3, 2, 1, 4

Question 22

Which of the following equations correctly describes the water softening process?

Answer 22

Ca2+(aq) + 2HCO3- (aq) + Ca2+(aq) + 2OH-(aq) -> 2CaCO3(s) + 2H2O(l)

Question 23

Which of the following aluminum ores contains aluminum and no other metals?

Answer 23

Corundum

Question 24

Arrange the steps of the Bayer process of alumina production (from bauxite) in the correct order:

1. Al(OH)4- -> Al(OH)3 + OH-
2. Al(OH)3 + OH- -> Al(OH)4-; Al(O)OH + OH- + H2O -> Al(OH)4-
3. Al(OH)3 (heated) -> Al2O3 + H2O
4. AlCl3 + 3K(Hg)x(l) -> 3KCl(s) + Al(Hg)x(l)

Answer 24

2, 1, 3

Question 25

All of the following compounds are amphoteric except:

Answer 25

CaO