CHEM 1411 CHAPT 11

12) ________ are particularly polarizable. A) Small nonpolar molecules B) Small polar molecules C) Large nonpolar molecules D) Large polar molecules E) Large molecules, regardless of their polarity,

E

10) Which of the following has dispersion forces as its only intermolecular force? A) CH4 B) HCl C) C6H13NH2 D) NaCl E) CH3Cl

A

14) Elemental iodine (I2) is a solid at room temperature. What is the major attractive force that exists among different I2 molecules in the solid? A) London dispersion forces B) dipole-dipole rejections C) ionic-dipole interactions D) covalent-ionic interactions E) dipole-dipole attractions

A

17) Which one of the following substances will not have hydrogen bonding as one of its intermolecular forces? A) B) C) D) E)

A

22) What type(s) of intermolecular forces exist between Br2 and CCl4? A) dispersion forces B) dispersion forces and ion-dipole C) dispersion forces and dipole-dipole D) dispersion forces, ion-dipole, and dipole-dipole E) None. Since both are gases at room temperature, they do not interact with each other.

A

28) How high a liquid will rise up a narrow tube as a result of capillary action depends on ________. A) the magnitudes of cohesive forces in the liquid and adhesive forces between the liquid and the tube, and gravity B) gravity alone C) only the magnitude of adhesive forces between the liquid and the tube D) the viscosity of the liquid E) only the magnitude of cohesive forces in the liquid

A

32) The phase changes B → C and D → E are not associated with temperature increases because the heat energy is used up to ________. A) increase distances between molecules B) break intramolecular bonds C) rearrange atoms within molecules D) increase the velocity of molecules E) increase the density of the sample

A

37) The substance with the largest heat of vaporization is ________. A) I2 B) Br2 C) Cl2 D) F2 E) O2

A

4) A gas is ________ and assumes ________ of its container, whereas a liquid is ________ and assumes ________ of its container. A) compressible, the volume and shape, not compressible, the shape of a portion B) compressible, the shape, not compressible, the volume and shape C) compressible, the volume and shape, compressible, the volume D) condensed, the volume and shape, condensed, the volume and shape E) condensed, the shape, compressible, the volume and shape Answer: A

A

42) Some things take longer to cook at high altitudes than at low altitudes because ________. A) water boils at a lower temperature at high altitude than at low altitude B) water boils at a higher temperature at high altitude than at low altitude C) heat isn't conducted as well in low density air D) natural gas flames don't burn as hot at high altitudes E) there is a higher moisture content in the air at high altitude

A

47) When the phase diagram for a substance has a solid-liquid phase boundary line that has a negative slope (leans to the left), the substance ________. A) can go from solid to liquid, within a small temperature range, via the application of pressure B) sublimes rather than melts under ordinary conditions C) cannot go from solid to liquid by application of pressure at any temperature D) cannot be liquefied above its triple point E) melts rather than sublimes under ordinary conditions

A

1) Crystalline solids ________. A) have their particles arranged randomly B) have highly ordered structures C) are usually very soft D) exist only at high temperatures E) exist only at very low temperatures

B

24) ________ is the energy required to expand the surface area of a liquid by a unit amount of area. A) Viscosity B) Surface tension C) Volatility D) Meniscus E) Capillary action

B

27) Viscosity is ________. A) the "skin" on a liquid surface caused by intermolecular attraction B) the resistance to flow C) the same as density D) inversely proportional to molar mass E) unaffected by temperature

B

30) Heat of sublimation can be approximated by adding together ________ and ________. A) heat of fusion, heat of condensation B) heat of fusion, heat of vaporization C) heat of freezing (solidification), heat of condensation D) heat of freezing (solidification), heat of vaporization E) heat of deposition, heat of vaporization

B

43) The vapor pressure of a liquid ________. A) increases linearly with increasing temperature B) increases nonlinearly with increasing temperature C) decreases linearly with increasing temperature D) decreases nonlinearly with increasing temperature E) is totally unrelated to its molecular structure

B

45) On a phase diagram, the critical temperature is ________. A) the temperature below which a gas cannot be liquefied B) the temperature above which a gas cannot be liquefied C) the temperature at which all three states are in equilibrium D) the temperature required to melt a solid E) the temperature required to cause sublimation of a solid

B

50) Which of the following characteristics would prevent liquid crystal behavior? A) long axial structure B) ionic configuration C) carbon-carbon single bonds D) double bonding E) polar groups

B

7) The strongest interparticle attractions exist between particles of a ________, and the weakest interparticle attractions exist between particles of a ________. A) solid, liquid B) solid, gas C) liquid, gas D) liquid, solid E) gas, solid

B

13) The intermolecular force(s) responsible for the fact that CH4 has the lowest boiling point in the set CH4, SiH4, GeH4, SnH4 is/are ________. A) hydrogen bonding B) dipole-dipole interactions C) London dispersion forces D) mainly hydrogen bonding but also dipole-dipole interactions E) mainly London-dispersion forces but also dipole-dipole interactions

C

15) Hydrogen bonding is a special case of ________. A) London-dispersion forces B) ion-dipole attraction C) dipole-dipole attractions D) ion-ion interactions E) none of the above

C

23) What types of intermolecular forces exist between NH3 and HF? A) dispersion forces and dipole-dipole forces B) dispersion forces and hydrogen bonds C) dispersion forces, dipole-dipole forces, and hydrogen bonds D) dispersion forces E) dispersion forces, hydrogen bonds, and ion-dipole forces

C

26) The shape of a liquid's meniscus is determined by ________. A) the viscosity of the liquid B) the type of material the container is made of C) the relative magnitudes of cohesive forces in the liquid and adhesive forces between the liquid and its container D) the amount of hydrogen bonding in the liquid E) the volume of the liquid

C

3) As a gaseous element condenses, the atoms become ________ and they have ________ attraction for one another. A) more separated, more B) more separated, less C) closer together, more D) closer together, less E) larger, greater

C

31) Which of the following statements is false? A) The absolute value of the heat of sublimation is equal to the absolute value of the heat of deposition. B) The heat of sublimation is equal to the sum of the heat of vaporization and the heat of melting. C) The heat of sublimation is equal to the sum of the heat of vaporization and the heat of freezing. D) The absolute value of the heat of sublimation is equal to the absolute value of the sum of the heat of condensation and the heat of freezing. E) The absolute value of the heat of deposition is equal to sum of the absolute value of the heat of vaporization and the absolute value of the heat of freezing.

C

34) Which compound has the strongest intermolecular forces? A) CBr4 B) C12H26 C) CI4 D) N2 E) O2

C

38) Of the following, ________ is an exothermic process. A) melting B) subliming C) freezing D) boiling E) All of the above are exothermic.

C

41) The vapor pressure of any substance at its normal boiling point is A) 1 Pa B) 1 torr C) 1 atm D) equal to atmospheric pressure E) equal to the vapor pressure of water

C

46) On a phase diagram, the melting point is the same as ________. A) the triple point B) the critical point C) the freezing point D) the boiling point E) the vapor-pressure curve

C

48) The predominant intermolecular force in CaBr2 is ________. A) London-dispersion forces B) ion-dipole forces C) ionic bonding D) dipole-dipole forces E) hydrogen bonding

C

5) Together, liquids and solids constitute ________ phases of matter. A) the compressible B) the fluid C) the condensed D) all of the E) the disordered GO: G2

C

11) When NaCl dissolves in water, aqueous Na+ and Cl- ions result. The force of attraction that exists between Na+ and H2O is called a(n) ________ interaction. A) dipole-dipole B) ion-ion C) hydrogen bonding D) ion-dipole E) London dispersion force

D

16) Which one of the following substances will have hydrogen bonding as one of its intermolecular forces? A) B) C) D) E)

D

21) What types of intermolecular forces exist between HI and H2S? A) dipole-dipole and ion-dipole B) dispersion forces, dipole-dipole, and ion-dipole C) dispersion forces, hydrogen bonding, dipole-dipole, and ion-dipole D) dispersion forces and dipole-dipole E) dispersion forces and ion-dipole

D

29) The property responsible for the "beading up" of water is ________. A) density B) viscosity C) vapor pressure D) surface tension E) hydrogen bonding

D

33) Based on the following information, which compound has the strongest intermolecular forces? Substance ΔHvap (kJ/mol) Argon (Ar) 6.3 Benzene (C6H6) 31.0 Ethanol (C2H5OH) 39.3 Water (H2O) 40.8 Methane (CH4) 9.2 A) Argon B) Benzene C) Ethanol D) Water E) Methane

D

8) Of the following substances, only ________ has London dispersion forces as the only intermolecular force. A) CH3OH B) NH3 C) H2S D) Kr E) HCl

D

9) In which of the following molecules is hydrogen bonding likely to be the most significant component of the total intermolecular forces? A) CH4 B) C5H11OH C) C6H13NH2 D) CH3OH E) CO2

D

18) The predominant intermolecular force in (CH3)2NH is ________. A) London dispersion forces B) ion-dipole forces C) ionic bonding D) dipole-dipole forces E) hydrogen bonding

E

19) Which of the following molecules has hydrogen bonding as its only intermolecular force? A) HF B) H2O C) C6H13NH2 D) C5H11OH E) None, all of the above exhibit dispersion forces.

E

2) In liquids, the attractive intermolecular forces are ________. A) very weak compared with kinetic energies of the molecules B) strong enough to hold molecules relatively close together C) strong enough to keep the molecules confined to vibrating about their fixed lattice points D) not strong enough to keep molecules from moving past each other E) strong enough to hold molecules relatively close together but not strong enough to keep molecules from moving past each other

E

20) Which of the following molecules has hydrogen bonding as its only intermolecular force? A) NH3 B) H2O C) C3H7OH D) HOCH2CH2OH E) None, all of the above exhibit dispersion forces.

E

25) Which statements about viscosity are true? (i) Viscosity increases as temperature decreases. (ii) Viscosity increases as molecular weight increases. (iii) Viscosity increases as intermolecular forces increase. A) (i) only B) (ii) and (iii) C) (i) and (iii) D) none E) all

E

35) A substance that expands to fill its container yet has a density approaching that of a liquid, and that can behave as a solvent is called a(n) ________. A) plasma B) gas C) liquid D) amorphous solid E) supercritical fluid and gas

E

36) The critical temperature and pressure of CS2 are 279 °C and 78 atm, respectively. At temperatures above 279 °C and pressures above 78 atm, CS2 can only occur as a ________. A) solid B) liquid C) liquid and gas D) gas E) supercritical fluid

E

39) A volatile liquid is one that ________. A) is highly flammable B) is highly viscous C) is highly hydrogen-bonded D) is highly cohesive E) readily evaporates

E

40) In general, the vapor pressure of a substance increases as ________ increases. A) surface tension B) molecular weight C) hydrogen bonding D) viscosity E) temperature

E

44) On a phase diagram, the critical pressure is ________. A) the pressure required to melt a solid B) the pressure below which a substance is a solid at all temperatures C) the pressure above which a substance is a liquid at all temperatures D) the pressure at which a liquid changes to a gas E) the pressure required to liquefy a gas at its critical temperature

E

49) Which of the following is most likely to exhibit liquid-crystalline behavior? A) CH3CH2-C(CH3)2-CH2CH3 B) CH3CH2CH2CH2CH2CH2CH2CH3 C) CH3CH2CH2CH2CH2- D) E)

E

6) Which statement is true about liquids but not true about solids? A) They flow and are highly ordered. B) They are highly ordered and not compressible. C) They flow and are compressible. D) They assume both the volume and the shape of their containers. E) They flow and are not compressible.

E