Chemistry Chapter 7 A change of state from a gas to a liquid is called

Introductory Chemistry: Atoms First, 5e (Russo/Silver)

Chapter 7 Intermolecular Forces and the Phases of Matter

7.1 Multiple-Choice Questions

1) Which of the three phases of matter (solid, liquid, or gas) has particles moving at the highest

average velocity?

A) solid

B) liquid

C) gas

D) The particles in all three phases have about the same average speed.

2) Which of the three phases of matter (solid, liquid, or gas) has particles separated by the least

amount of distance?

A) solid

B) liquid

C) gas

D) The separation distance is about the same in all three phases.

3) Which of the three phases of matter (solid, liquid, or gas) has particles that are fast-moving

and independent of each other?

A) solid

B) liquid

C) gas

D) All of the above feature loose arrangements of particles.

4) Which of the three phases of matter (solid, liquid, or gas) features particles in a fixed, rigid

arrangement?

A) solid

B) liquid

C) gas

D) All three phases of matter have rigid arrangements of particles.

5) Which of the three phases of matter (solid, liquid, or gas) features particles that are easily

compressible?

A) solid

B) liquid

C) gas

D) All three phases of matter are compressible.

6) Which of the three phases of matter (solid, liquid, or gas) features particles that are no longer

held together by intermolecular forces?

A) solid

B) liquid

C) gas

D) All three phases of matter will do this.

7) A change of state from a gas to a liquid is called ________.

A) sublimation

B) condensation

C) evaporation

D) melting

8) The change of state from a liquid to a gas is called ________.

A) sublimation

B) condensation

C) evaporation

D) melting

9) The change of state from a solid to a gas is called ________.

A) melting

B) sublimation

C) evaporation

D) condensation

10) The change of state from a solid to a liquid is called ________.

A) melting

B) sublimation

C) evaporation

D) condensation

11) Which of the following statements is true about intermolecular forces of attraction between

molecules?

A) They tend to hold molecules together.

B) Cooling is responsible for the substance’s liquefaction.

C) The solidification of a substance usually requires lower temperatures than in the case of

liquefaction.

D) All of the above are true.

12) The term “normal” boiling point indicates ________.

A) the temperature at which a liquid evaporates under the atmospheric pressure found at sea

level.

B) the temperature at which a liquid boils under the atmospheric pressure found at sea level.

C) the temperature at which a liquid boils under any pressure conditions

D) both A and B

13) Which of the following chemical substances would you expect to have the lowest boiling

point (you may consider molecular mass and the degree of intermolecular forces as primary

controlling factors)?

A) CH4

B) CH3CH3

C) CH3CH2CH3

D) CH3CH2CH2CH3

14) Between individual molecules of NO2 in the solid state, which of the following types of

intermolecular forces would you expect to be dominant?

A) hydrogen bonding

B) London forces

C) van der Waals forces

D) dipole-dipole forces

15) Which of the following substances would you expect to be a liquid at room temperature,

assuming that strong intermolecular forces need to be present to be a liquid at room temperature?

A) N2

B) CS2

C) H2

D) O2

16) Which of the following chemical substances would you expect to have the highest melting

point?

A) water, H2O

B) methyl alcohol, CH3OH

C) nitrogen dioxide, NO2

D) hydrogen sulfide, H2S

17) Which of the following sublimes?

A) sugar

B) iron

C) mothballs

D) margarine

18) Which of the following does not sublime?

A) mothballs

B) iodine crystals

C) salt

D) dry ice

19) Which of the following is not a solid at 0 °C?

A) salt

B) carbon dioxide

C) sugar

D) iron

20) Which of the following statements about London forces is correct?

A) London forces are also called dispersion forces.

B) London forces are relatively weakly attractive.

C) London forces occur between polar and nonpolar molecules.

D) All the above statements are true.

21) Nonpolar molecules may exhibit ________.

A) London forces

B) hydrogen bonding

C) dipolar forces

D) all of the above

22) Polar molecules may exhibit ________.

A) London forces

B) hydrogen bonding

C) dipole-dipole forces

D) all of the above

23) London forces are extremely weak for ________.

A) nitrogen gas

B) methane gas

C) oxygen gas

D) all of the above

24) Which of the following experiences the strongest London forces?

A) carbon tetrachloride

B) water

C) hydrogen

D) helium

25) The main reason why carbon tetrabromide is a solid at room temperature when compared to

carbon tetrachloride which is a liquid is because ________.

A) carbon tetrabromide is tetrahedral in shape.

B) carbon tetrachloride has the weaker London forces than carbon tetrabromide.

C) carbon tetrabromide may undergo hydrogen bonding.

D) all of the above

26) Which of the following chemical substances would you expect to have the highest boiling

point (you may consider molecular mass and the degree of intermolecular hydrogen bonding as

primary controlling factors)?

A) methane, CH4

B) ammonia, NH3

C) methyl alcohol, CH3OH

D) ethyl alcohol, CH3CH2OH

27) Which of the following chemical substances would you expect to exhibit hydrogen bonding?

A) methyl chloride, CH3Cl

B) methyl alcohol, CH3OH

C) octane, C8H18

D) methane, CH4

28) Which of the following chemical substances would you expect to exhibit hydrogen bonding?

A) NH3

B) CH3OH

C) HF

D) all of the above

29) Which of the compounds below has a large permanent dipole?

A) methane

B) hydrogen

C) acetone

D) nitrogen

30) Which of the following does not have a dipole?

A) carbon tetrachloride

B) acetone

C) ammonia

D) water

31) The strength of an O-H bond is about equal to ________ kJ/bond

A) 16

B) 50

C) 100

D) 400

32) The strength of a hydrogen bond is about ________ percent of the strength of a normal O-H

bond

A) 1

B) 4

C) 16

D) 50

33) To form hydrogen bonds, molecules must contain ________.

A) an N-H bond

B) an O-H bond

C) an H-F bond

D) at least one of the above mentioned bonds

34) Which of the following will have the highest boiling point?

A) CH3OCH3

B) CH3CH2OH

C) HOCH2–CH2OH

D) CH3CH3

35) Which of the following will have the lowest boiling point?

A) CH3OCH3

B) CH3CH2OH

C) HOCH2–CH2OH

D) CH3CH3

36) The force(s) responsible for holding the DNA molecule in a very long twisted zipper is

________.

A) hydrogen bonding

B) London forces

C) dipolar forces

D) interionic forces

37) Which of the following will have the highest boiling point?

A) HI

B) HBr

C) HCl

D) HF

38) Which of the following will have the lowest boiling point?

A) H2S

B) H2Te

C) H2Se

D) H2O

39) Which of the following influences the strength of the intermolecular forces?

A) distance between interacting molecules

B) relative orientation between interacting molecules

C) location of the molecule in a liquid or solid

D) All of the above influence the strength of the intermolecular forces.

40) Which of the following intermolecular force is the strongest?

A) London forces

B) van der Waals forces

C) hydrogen bonding

D) dipole forces

41) How does vancomycin function to kill bacteria?

A) destroys the bacterial DNA

B) interferes with cell wall construction

C) inhibits protein synthesis

D) prevents bacteria metabolism

42) Which intermolecular force is important for the function of the antibiotic vancomycin?

A) London forces

B) van der Waals forces

C) hydrogen bonding

D) dipole forces