Deck 11: Liquids and Intermolecular Forces

Question 1

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

Answer 1

dipole-dipole attractions

Question 2

Which species has London dispersion forces as the only intermolecular force?

A)KBr
B)HI
C)CH₃OH
D)CH₃CH₃
E)CH₃F

Answer 2

CH₃CH₃

Question 3

________ 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,

Answer 3

Large molecules, regardless of their polarity,

Question 4

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

Question 5

Crystalline solids ________.

A)have their particles arranged randomly
B)have ordered structures
C)are usually very soft
D)exist only at high temperatures
E)exist only at very low temperatures

Question 6

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

Question 7

The intermolecular force(s)responsible for the fact that CH₄ has the lowest boiling point in the set CH₄,CH₃CH₃,CH₃CH₂CH₃,CH₃CH₂CH₂CH₃ is/are ________.

A)hydrogen bonding
B)London dispersion forces
C)mainly hydrogen bonding but also dipole-dipole interactions
D)dipole-dipole interactions
E)mainly London-dispersion forces but also dipole-dipole interactions

Question 8

Which species has London dispersion forces as the only intermolecular force?

A)CH₃CH₂OH
B)Ar
C)NH₃
D)HBr
E)H₂O

Question 9

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.

Question 10

The ease with which the charge distribution in a molecule can be distorted by an external electrical field is called the ________.

A)electronegativity
B)hydrogen bonding
C)polarizability
D)volatility
E)viscosity

Question 11

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

Question 12

Which molecule has hydrogen bonding as the predominant intermolecular force?

A)CH₄
B)C₆H₆
C)CH₃OH
D)CO₂
E)C₄H₁₀

Question 13

Together,liquids and solids constitute ________ phases of matter.

A)the compressible
B)the fluid
C)the condensed
D)all of the
E)the disordered

Question 14

The predominant intermolecular force in water is ________.

A)London dispersion forces
B)hydrogen bonding
C)ion-dipole forces
D)dipole-dipole forces
E)ionic bonding

Question 15

Which one of the following substances will have hydrogen bonding as one of its intermolecular forces?

A)
B)
C)
D)
E)

Question 16

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 interactions
C)ionic-dipole interactions
D)covalent-ionic interactions
E)dipole-dipole attractions

Question 17

Which one of the following substances will not have hydrogen bonding as one of its intermolecular forces?

A)
B)
C)
D)
E)

Question 18

What intermolecular force is responsible for the fact that ice is less dense than liquid water?

A)London dispersion forces
B)dipole-dipole forces
C)ion-dipole forces
D)hydrogen bonding
E)ionic bonding

Question 19

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

Question 20

When KBr dissolves in water,aqueous K⁺ and Br^- ions result.The force of attraction that exists between K⁺ and H₂O is called a(n)________ interaction.

A)dipole-dipole
B)ion-dipole
C)ion-ion
D)London dispersion force
E)hydrogen bonding

Question 21

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 deposition.
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.

Question 22

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

Question 23

What types of intermolecular forces exist between water and HF?

A)dispersion forces and dipole-dipole forces
B)dispersion forces, dipole-dipole forces, and hydrogen bonds
C)dispersion forces and hydrogen bonds
D)dispersion forces
E)dispersion forces, hydrogen bonds, and ion-dipole forces

Question 24

The ________ (is)are associated with the heat energy being used up to increase distances between molecules.

A)phase change B → C
B)phase changes B → C and D → E
C)phase change D → E
D)phase change B → E
E)phase change C → E

Question 25

Large intermolecular forces in a substance are manifested by ________.

A)low vapor pressure
B)high boiling point
C)high heats of fusion and vaporization
D)high critical temperatures and pressures
E)all of the above

Question 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

Question 27

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

Question 28

The property responsible for the "beading up" of water is ________.

A)density
B)viscosity
C)vapor pressure
D)surface tension
E)hydrogen bonding

Question 29

________ 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

Question 30

Which compound has the strongest intermolecular forces?

A)CCl₄
B)CI₄
C)CH₄
D)H₂
E)O₂

Question 31

Based on the following information,which compound has the strongest intermolecular forces?
Substance ΔH_vap (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

Question 32

Which of the following molecules has hydrogen bonding as its only intermolecular force?

A)HCl
B)NH₃
C)H₂O
D)CH₃OH
E)None, all of the above exhibit dispersion forces.

Question 33

What types of intermolecular forces exist between CH₃OH and H₂O?

A)dipole-dipole and ion-dipole
B)dispersion forces, dipole-dipole, and hydrogen bonding
C)dispersion forces, dipole-dipole, and ion-dipole
D)dispersion forces, hydrogen bonding, dipole-dipole, and ion-dipole
E)dispersion forces and ion-dipole

Question 34

What type(s)of intermolecular forces exist between Cl₂ and CCl₄?

A)dispersion forces and ion-dipole
B)dispersion forces and dipole-dipole
C)dispersion forces
D)dispersion forces, ion-dipole, and dipole-dipole
E)None. Since both are gases at room temperature, they do not interact with each other.

Question 35

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

Question 36

Which of the following molecules has London Forces as its only intermolecular force?

A)H₂O
B)CH₃CH₂NH₂
C)HOCH₂CH₂OH
D)CH₃CH₃
E)None, all of the above exhibit dispersion forces.

Question 37

What types of intermolecular forces exist between NH₃ and H₂O?

A)dispersion forces
B)dispersion forces and hydrogen bonds
C)dispersion forces and ion-dipole forces
D)dispersion forces, dipole-dipole forces, and hydrogen bonds
E)dispersion forces, hydrogen bonds, and ion-dipole forces

Question 38

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

Question 39

Octane C₈H₁₈ molecules are held together by ________.

A)ion-ion interactions
B)hydrogen bonding
C)ion-dipole interactions
D)London dispersion forces
E)dipole-dipole interactions

Question 40

What type(s)of intermolecular forces exist between NH₃ and PO₄^3-?

A)dispersion forces
B)dispersion forces, ion-dipole, and dipole-dipole
C)dispersion forces and dipole-dipole
D)dispersion forces and ion-dipole
E)dispersion forces, ion-dipole, dipole-dipole, and hydrogen bonds

Question 41

In the ________ liquid-crystalline phase,the molecules are arranged in sheets,with their long axes parallel and their ends aligned as well.

A)smectic B
B)smectic C
C)smectic A
D)smectic E
E)smectic D

Question 42

A supercritical fluid can expand like a ________ to fill a container and has a density similar to that of a ________ so can behave as a solvent.

A)gas, plasma
B)gas, solid
C)solid, gas
D)liquid, gas
E)gas, liquid

Question 43

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

Question 44

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

Question 45

When the phase diagram for a substance has a solid-liquid phase boundary line that has a ________ slope,the substance can go from solid to liquid,within a small temperature range,via the application of pressure.

A)positive
B)zero
C)y = 1
D)negative
E)y = 0

Question 46

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

Question 47

Of the following,________ is an exothermic process.

A)melting
B)subliming
C)freezing
D)boiling
E)All of the above are exothermic.

Question 48

Volatility and vapor pressure are ________.

A)inversely proportional to one another
B)directly proportional to one another
C)not related
D)the same thing
E)both independent of temperature

Question 49

The substance with the largest heat of vaporization is ________.

A)H₂
B)Cl₂
C)I₂
D)N₂
E)O₂

Question 50

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

Question 51

Which of the following is most likely to exhibit liquid-crystalline behavior?

A)CH₃CH₂-C(CH₃)₂-CH₂CH₃
B)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₃
C)CH₃CH₂CH₂CH₂CH₂^-
D)
E)

Question 52

In general,the vapor pressure of a substance increases as ________ increases.

A)surface tension
B)molecular weight
C)hydrogen bonding
D)viscosity
E)temperature

Question 53

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

Question 54

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

Question 55

All of the following are characteristics of liquid crystal behavior except ________.

A)long axial structure
B)carbon-carbon single bonds
C)double bonding
D)ionic configuration
E)polar groups

Question 56

The critical temperature and pressure of CS₂ are 279 °C and 78 atm,respectively.A supercritical fluid can only exist at a temperature ________ 279 °C and pressure ________ 78 atm.

A)exactly, exactly
B)above, below
C)above, above
D)below, above
E)below, below

Question 57

The predominant intramolecular force in CaBr₂ is ________.

A)London-dispersion forces
B)ion-dipole forces
C)ionic bonding
D)dipole-dipole forces
E)hydrogen bonding

Question 58

Of the following,________ should have the highest critical temperature.

A)CBr₄
B)CCl₄
C)CF₄
D)CH₄
E)H₂

Question 59

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

Question 60

- is the slope of a plot of the natural log of the vapor pressure of a substance versus ________.

A)-1/T
B)-T
C)1/T
D)T
E)2T

Question 61

According to the phase diagram shown above,what is the normal melting point (°C)?

A)15
B)25
C)35
D)45
E)55

Question 62

The heating curve shown was generated by measuring the heat flow and temperature for a solid as it was heated.The slope of the E-F segment corresponds to the heat capacity of the ________.

A)liquid-gas
B)solid-gas
C)gas
D)solid
E)liquid

Question 63

Molecules with ________ do not generally exhibit liquid-crystalline properties because they lack the rigidity necessary for alignment.

A)both single and double bonds
B)double or triple bonds
C)single, double, and triple bonds
D)only single bonds
E)only single and double bonds

Question 64

In the ________ liquid crystalline phase,the component molecules exhibit ________ dimensional ordering.

A)nematic, one
B)smectic A, one
C)nematic, two
D)nematic, three
E)smectic B, one

Question 65

The phase diagram of a substance is given above.The region that corresponds to the solid phase is ________.

A)w
B)x
C)y
D)z
E)x and y

Question 66

The heating curve shown was generated by measuring the heat flow and temperature for a solid as it was heated.The slope of the ________ segment corresponds to the heat capacity of the liquid of the substance.

A)AB
B)BC
C)CD
D)DE
E)EF

Question 67

Based on molecular mass and dipole moment of the five compounds in the table below,which should have the highest boiling point?

A)CH₃CH₂CH₃
B)CH₃OCH₃
C)CH₃Cl
D)CH₃CHO
E)CH₃CN

Question 68

On the phase diagram shown above,segment ________ corresponds to the conditions of temperature and pressure under which the solid and the gas of the substance are in equilibrium.

A)AB
B)AC
C)AD
D)CD
E)BC

Question 69

On the phase diagram shown above,the coordinates of point B corresponds to the ________.

A)critical temperature and pressure
B)critical pressure
C)critical temperature
D)boiling point
E)triple point

Question 70

For a given substance that exhibits liquid-crystalline properties,the transition from solid to liquid-crystal state occurs ________.

A)over a range of temperatures between the melting point of the solid and the boiling point of the liquid
B)at the melting point of the solid
C)over a range of temperatures that includes the melting point of the solid
D)at a well-defined temperature above the melting point of the solid
E)at a well-defined temperature below the melting point of the solid

Question 71

________ liquid crystals are colored because the molecular layers are arranged in slightly twisted planes with respect to one another.

A)smectic B
B)cholesteric
C)smectic A
D)smectic C
E)smectic D

Question 72

The phase diagram of a substance is shown above.The area labeled ________ indicates the gas phase for the substance.

A)w
B)x
C)y
D)z
E)y and z

Question 73

On the phase diagram shown above,the coordinates of point ________ correspond to the triple point.

A)A
B)B
C)C
D)D
E)E

Question 74

The heating curve shown was generated by measuring the heat flow and temperature for a solid as it was heated.The slope of the ________ segment corresponds to the heat capacity of the solid.

A)AB
B)BC
C)CD
D)DE
E)EF

Question 75

The phase diagram of a substance is shown above.The area labeled ________ indicates the solid phase for the substance.

A)w
B)x
C)y
D)z
E)y and z

Question 76

There are ________ types of smectic liquid-crystalline phases.

A)6
B)5
C)2
D)3
E)4

Question 77

The heating curve shown was generated by measuring the heat flow and temperature of a solid as it was heated.The heat flow into the sample in the segment ________ will yield the value of the ΔH_fusion of this substance.

A)AB
B)BC
C)CD
D)DE
E)EF

Question 78

According to the phase diagram shown above,what is the normal boiling point (°C)?

A)10
B)20
C)30
D)40
E)50

Question 79

The heating curve shown was generated by measuring the heat flow and temperature of a solid as it was heated.The heat flow into the sample in the segment D-E will yield the value of the ________ of this substance.

A)ΔH_sub
B)ΔH_vap
C)ΔH_melting
D)ΔH_fusion
E)ΔH_rxn

Question 80

What are the common types of smectic liquid-crystalline phases?

A)A, C, and D
B)A only
C)A and C
D)A and D
E)C and D