Some Review Name___________________

Mr. Bennett

What type(s) of intermolecular forces exist (and why you chose it) between the following pairs:

a. NH3 and CCl4 c. H2 and SO4-2

b. CaF2 and CH4 d. NH3 and H2O

Name the intermolecular forces (and why you chose it) existing in:

a. C6H6 e. SiO2

b. CH3COOH f. NH3

c. CH3Cl g. HF

d. O3 h. NaCl

Describe the solution process at the molecular level.

Arrange these in order of increasing solubility in water: N2, I2, NaCl, NH3

Remember: You are responsible for the end of Chapter 11.

Dispersion

Dipole-Dipole

Dipole-Induced dipole

Ion-Dipole

Ion-Induced dipole

Hydrogen bonds

AP Chemistry Free Response

1

2008 part B, form A, question #6

Answer the following questions by using principles of molecular structure and intermolecular forces.

(a) Structures of the pyridine molecule and the benzene molecule are shown below. Pyridine is soluble in water, whereas benzene

is not soluble in water. Account for the difference in solubility. You must discuss both of the substances in your answer.

(b) Structures of the dimethyl ether molecule and the ethanol molecule are shown below. The normal boiling point of dimethyl

ether is 250 K, whereas the normal boiling point of ethanol is 351 K. Account for the difference in boiling points. You must

discuss both of the substances in your answer.

(c) SO2 melts at 201 K, whereas SiO2 melts at 1,883 K. Account for the difference in melting points. You must discuss both of the

substances in your answer.

(d) The normal boiling point of Cl2(l) (238 K) is higher than the normal boiling point of HCl(l) (188 K). Account for the difference

in normal boiling points based on the types of intermolecular forces in the substances. You must discuss both of the substances

in your answer.

2006 D Required

Answer each of the following in terms of principles of molecular behavior and chemical concepts.

(a) The structures for glucose, C6H12O6, and cyclohexane, C6H12, are shown below.

Identify the type(s) of intermolecular attractive forces in

(i) pure glucose

(ii) pure cyclohexane

(b) Glucose is soluble in water but cyclohexane is not soluble in water. Explain.

(c) Consider the two processes represented below.

Process 1: H2O(l) H2O(g) ∆H˚ = +44.0 kJ mol-1

Process 2: H2O(l) H2(g) + 1

2 O2(g) ∆H˚ = +286 kJ mol-1

(i) For each of the two processes, identify the type(s) of intermolecular or intramolecular attractive forces that must be

overcome for the process to occur.

(ii) Indicate whether you agree or disagree with the statement in the box below. Support your answer with a short

explanation.

When water boils, H2O molecules break apart to form

hydrogen molecules and oxygen molecules.

AP Chemistry Free Response

2

(d) Consider the four reaction-energy profile diagrams shown below.

(i) Identify the two diagrams that could represent a catalyzed and an uncatalyzed reaction pathway for the same reaction.

Indicate which of the two diagrams represents the catalyzed reaction pathway for the reaction.

(ii) Indicate whether you agree or disagree with the statement in the box below. Support your answer with a short

explanation.

Adding a catalyst to a reaction mixture adds energy that

causes the reaction to proceed more quickly.

2005 D Use principles of atomic structure, bonding and/or intermolecular forces to respond to each of the following. Your responses

must include specific information about all substances referred to in each question.

(a) At a pressure of 1 atm, the boiling point of NH3(l) is 240 K, whereas the boiling point of NF3(l) is 144 K.

(i) Identify the intermolecular forces(s) in each substance.

(ii) Account for the difference in the boiling points of the substances.

(b) The melting point of KCl(s) is 776˚C, whereas the melting point of NaCl(s) is 801˚C.

(i) Identify the type of bonding in each substance.

(ii) Account for the difference in the melting points of the substances.

(c) As shown in the table below, the first ionization energies of Si, P, and Cl show a trend.

Element First Ionization Energy (kJ

mol-1)

Si 786

P 1012

Cl 1251

(i) For each of the three elements, identify the quantum level (e.g., n =1, n = 2, etc.) of the valence electrons in the atom.

(ii) Explain the reasons for the trend in the first ionization energy.

(d) A certain element has two stable isotopes. The mass of one of the isotopes is 62.93 amu and the mass of the other isotope is

64.93 amu.

(i) Identify the element. Justify your answer.

(ii) Which isotope is more abundant? Justify your answer.

2004 D Use appropriate chemical principles to account for each of the following observations. In each part, your response must

include specific information about both substances.

(a) At 25˚ C and 1 atm, F2 is a gas whereas I2 is a solid.

(b) The melting point of NaF is 993˚ C, whereas the melting point of CsCl is 645˚.

(c) The shape of ICl4– ion is square planar, whereas the shape of BF4

– ion is tetrahedral.

(d) Ammonia, NH3, is very soluble in water, whereas phosphine, PH3, is only moderately soluble in water.

2001 D

Account for each of the following observations about pairs of substances. In your answers, use appropriate principles of chemical

bonding and/or intermolecular forces. In each part, your answer must include references to both substances.

AP Chemistry Free Response

3

(a) Even though NH3 and CH4 have similar molecular masses, NH3 has a much higher normal boiling point (-33C) than CH4 (-

164C).

(b) At 25C and 1.0 atm, ethane (C2H6) is a gas and hexane (C6H14) is a liquid.

(c) Si melts at a much higher temperature (1,410C) than Cl2 (-101C).

(d) MgO melts at a much higher temperature (2,852C) than NaF (993C).

1992 D

Explain each of the following in terms of atomic and molecular structures and/or intermolecular forces.

(a) Solid K conducts an electric current, whereas solid KNO3 does not.

(b) SbCl3 has measurable dipole moment, whereas SbCl5 does not.

(c) The normal boiling point of CCl4 is 77ºC, whereas that of CBr4 is 190ºC.

(d) NaI(s) is very soluble in water, whereas I2(s) has a solubility of only 0.03 gram per 100 grams of water.

1988 D

Using principles of chemical bonding and/or intermolecular forces, explain each of the following.

(a) Xenon has a higher boiling point than neon has.

(b) Solid copper is an excellent conductor of electricity, but solid copper chloride is not.

(c) SiO2 melts at a very high temperature, while CO2 is a gas at room temperature, even though Si and C are in the same chemical

family.

(d) Molecules of NF3 are polar, but those of BF3 are not.

1979 D

Butane, chloroethane, acetone, and 1-propanol all have approximately the same molecular weights. Data on their boiling points

and solubilities in water are listed in the table below.

Compound

Formula

Boiling

Pt.(ºC)

Solubility in

water

Butane CH3CH2CH2CH3 0 insoluble

Chloroethane CH3CH2Cl 12 insoluble

Acetone

CH3C CH3

56 completely

miscible

1-Propanol

CH3CH2CH2OH

97

completely

miscible

On the basis of dipole moments (molecular polarities) and/or hydrogen bonding, explain in a qualitative way the differences in the

(a) boiling points of butane and chloroethane.

(b) water solubilities of chloroethane and acetone.

(c) water solubilities of butane and 1-propanol.

(d) boiling points of acetone and 1-propanol.

1974 D The boiling points of the following compounds increase in the order in which they are listed below:

CH4 < H2S < NH3

Discuss the theoretical considerations involved and use them to account for this order.

C

||

O

AP Chemistry: Solutions Name ____________________________

43. Which of the following does NOT behave as an electrolyte when it is dissolved in water?

(A) CH3OH (B) K2CO3 (C) NH4Br (D) HI (E) Sodium acetate, CH3COONa

47. Which of the following has the lowest conductivity?

(A) 0.1 M CuSO4 (B) 0.1 M KOH (C) 0.1 M BaCl2 (D) 0.1 M HF (E) 0.1 M HNO3

53. If 87 grams of K2 SO4 (molar mass 174 grams) is dissolved in enough water to make 250 milliliters of solution, what are the

concentrations of the potassium and the sulfate ions?

[K+] [SO42−]

(A) 0.020 M 0.020 M

(B) 1.0 M 2.0 M

(C) 2.0 M 1.0 M

(D) 2.0 M 2.0 M

(E) 4.0 M 2.0 M

73. The volume of distilled water that should be added to 10.0 mL of 6.00 M HCl(aq) in order to prepare a 0.500 M HCl(aq) solution is

approximately…

(A) 50.0 mL (B) 60.0 mL (C) 100. mL (D) 110. mL (E) 120. mL

28. Which of the following is probably true for a solid solute with a highly endothermic heat of solution when dissolved in water?

(A) The solid has a low lattice energy.

(B) As the solute dissolves, the temperature of the solution increases.

(C) The resulting solution is ideal.

(D) The solid is more soluble at higher temperatures.

(E) the solid has a high energy of hydration.

31. If the temperature of an aqueous solution of NaCl is increased from 20 °C to 90 °C, which of the following statements is true?

(A) The density of the solution remains unchanged. (B) The molarity of the solution remains unchanged.

(C) The molality of the solution remains unchanged. (D) The mole fraction of solute decreases.

(E) The mole fraction of solute increases.

67. Substances X and Y that were in a solution were separated in the laboratory using the technique of fractional crystallization. This

fractional crystallization is possible because substances X and Y have different…

(A) boiling points (B) melting points (C) densities (D) crystal colors (E) solubilities

38. A 0.10 M aqueous solution of sodium sulfate, Na2SO4, is a better conductor of electricity than a 0.10 M aqueous solution of

sodium chloride, NaCl. Which of the following best explains this observation?

(A) Na2SO4 is more soluble in water than NaCl is.

(B) Na2SO4 has a higher molar mass than NaCl has.

(C) To prepare a given volume of 0.10 M solution, the mass of Na2SO4 needed is more than twice the mass of ……NaCl needed.

(D) More moles of ions are present in a given volume of 0.10 M Na2SO4 than in the same volume of 0.10 M ……NaCl.

(E) The degree of dissociation of Na2SO4 in solution is significantly greater than that of NaCl.

Test Review Chapter 11 January 25, 2016

1

1. Dipole–dipole interactions are present in _____.

A) HCl

B) C6H6

C) CH4

D) NaCl

2. Hydration is an example of a(an)_____ interaction.

A) dipole–dipole

B) ion–dipole

C) van der Waals

D) dispersion

3. Non-polar atoms and molecules condense due to _____.

A) ion–dipole interaction

B) van der Waals forces

C) polarizability dispersion forces

D) dipole–dipole attraction

4. A compound having a permanent dipole moment is

_____.

A) CO2

B) H2

C) CH4

D) CO

5. Which element can take part in hydrogen bonding?

A) F

B) O

C) N

D) all of them

6. An element which does not take part in hydrogen

bonding is _____.

A) F

B) C

C) O

D) N

7. The hydrocarbon having the lowest boiling point is _____.

A) C4H10

B) CH4

C) C6H6

D) C2H6

8. The hydride having the highest boiling point is _____.

A) SiH4

B) GeH4

C) CH4

D) SnH4

9. Only dispersion forces are present in _____.

A) HF

B) C6H6

C) CO

D) C2H5OH

10. Ion–ion attractive forces are present in _____.

A) CS2

B) CO2

C) NaCl

D) CO

11. A compound which hydrogen bonds is _____.

A) BeH2

B) CH4

C) CH3COOH

D) C2H6

12. The compound having the lowest boiling point is __.

A) CH3Br

B) CH3OH

C) CO2

D) RbF

14. The correct order of boiling points is _____.

A) O2 > Cl2

B) Cl2 > O2

C) SO2 < CO2

D) HF < HI

15. The correct order of boiling points is _____.

A) Ne > Xe

B) CS2 > CO2

C) PH3 > NH3

D) H2S >H2O

16. Adhesion is the force of attraction between _____.

A) large molecules

B) smaller molecules

C) unlike molecules

D) like molecules

17. Cohesion is the force of attraction between __ molecules.

A) similar

B) like

C) unlike

D) small

Test Review Chapter 11 January 25, 2016

2

18. Viscosity is a measure of a fluid's _____.

A) reactance

B) resistance to flow

C) density

D) tension

19. The liquid having the highest viscosity is _____.

A) Hg

B) water

C) glycerol, HO-CH2-CH(OH)-CH2OH

D) ethanol, CH3-CH2OH

20. Which of the following factors increases the

viscosity?

A) increase of temperature

B) hydrogen bonding

C) less molecular attraction

D) less molecular weight

22. What happens when water freezes?

A) Its volume decreases

B) Its volume increases

C) Its density increases

D) hydrogen bonding becomes less ordered

23. The liquid having the greatest surface tension of the following is _____.

A) Ethanol, CH3CH2OH

B) diethyl ether, CH3OCH3

C) water

D) Methanol, CH3OH

24. The liquid having the greatest viscosity of the following is

_____.

A) water

B) ethylene glycol, OH-C2H4-OH

C) Acetone, CH3-CO-CH3

D) Ethanol, CH3CH2OH

48. A soft solid has a low melting point and does not

conduct current in solution or in a molten state. It is an

example of a/an _____ solid. A) covalent B) molecular C) ionic D) metallic

49. A very hard solid has a high melting point and

does not conduct current even in the molten

state. The solid could be a/an _____ solid.

A) ionic

B) metallic

C) molecular

D) covalent

53. Which of the following is not a metallic solid?

A) Cr

B) Ag

C) Ni

D) Ar

62. The vapor pressure of a liquid is _____.

A) inversely proportional to temperature

B) directly proportional to temperature

C) directly proportional to boiling point

D) directly proportional to melting point

65. Which of the following statements is correct? A) The greater the molecular weight, the lower the b.p B) The greater the molecular attraction, the higher the b.p

C) The greater the molecular attraction, the lower the HV

D) The smaller the molecular weight, the higher the b.p

66. The boiling point of a liquid depends on _____.

A) external pressure

B) molecular attraction

C) molecular weight

D) all of the above

69. Dry ice is solid _____.

A) SO2

B) NO2

C) H2O

D) CO2

70. The vapor pressure of a liquid depends on the ___.

A) amount of liquid

B) volume of the liquid

C) temperature of the liquid

D) surface area of the liquid

71. Which of the following has the highest boiling

point?

A) H2O

B) Hg

C) CH3OCH3

D) C2H5OH

73. The boiling point of the liquid can be changed by the

change of _____.

A) heat

B) volume

C) pressure

D) surface area

Test Review Chapter 11 January 25, 2016

3

75. Which of the following factors will not affect the

rate of vaporization of the liquid?

A) temperature

B) amount of liquid

C) intermolecular forces

D) surface area

77. A liquid having a higher vapor pressure will have _____.

A) higher molecular weight

B) lower boiling point

C) higher boiling point

D) higher surface area

81. A phase diagram is the plot of _____.

A) P vs T

B) V vs T

C) P vs V

D)

82. Phase(s) existing at the triple point is/are _____.

A) solid

B) solid, liquid

C) solid, liquid, vapor

D) solid, vapor

84. The force due to hydrogen bonding must be

overcome in the boiling of _____.

A) CH3OCH3

B) NH3

C) SbH3

D) C2H5OC2H5

85. Which of the following properties indicates very

strong intermolecular forces in liquids?

A) very low surface tension

B) very low critical temperature

C) very low boiling point

D) very low vapor pressure

89. Polarizability is highest for _____.

A) CH4

B) H2

C) CCl4

D) H2S

93. Lattice energy is highest for _____.

A) NaCl

B) NaBr

C) KCl

D) KBr

94. Which of the following statements is true?

A) Dipole–dipole interaction is greatest when

molecules have only temporary dipole moments

B) All compounds having hydrogen will have

hydrogen bonding

C) Dispersion forces are present on all atoms and

molecules

D) The extent of ion-induced dipole interaction

depends only on the charge of the ion

95. A drop of oil in water has a spherical shape due to __.

A) viscosity

B) density

C) surface tension

D) hydrogen bonding

96. The most ideal gas of the following is _____.

A) CH4

B) CO2

C) SO2

D) NH3

97. The substance having only dispersion forces is ___.

A) K2S

B) NF3

C) F2

D) OF2

98. The molecule not having dipole–dipole interactions

is _____.

A) NF3

B) OF2

C) NH3

D) N2

103. The correct order of viscosities is _____. A)

water > diethyl ether(C2H5OC2H5

B) glycerol < water

C) water < diethyl ether D) diethylether > glycerol

Test Review Chapter 11 January 25, 2016

4

Test Review Chapter 12 January 25, 2016

Page 1

3. The concept like dissolves like is based on _____.

A) surface tension

B) viscosity

C) intermolecular attraction

D) molecular weight

5. The interaction between a solute and a

solvent is called _____.

A) solution

B) solvation

C) solutation

D) saturation

6. In which of the following cases is the

solvation an ion-dipole interaction?

A) water + glucose(C6H12O6)

B) ether(CH3OCH3) + urea(CH4N2O)

C) water + NaCl

D) benzene(C6H6) + aniline(C6H5NH2)

7. Solvation is due to dispersion forces in the

case of _____.

A) ether – hexane(C5H12)

B) water – Na2SO4

C) water – HCl

D) water – glucose

9. A solution process will be endothermic if the

magnitude of the intermolecular interaction is in

the order _____.

A) solute–solvent > solvent–solvent

B) solute–solvent < solvent–solvent and solute–

solute

C) solute–solvent > solvent–solvent and solute–

solute

D) solvent–solvent < solute–solute

14. The increasing order of solubility in water of the

following substances is _____.

A) O2 < Br2 < LiCl < CH3OH

B) CH3OH < LiCl < Br2 < O2

C) CH3OH < Br2 < LiCl < O2

D) LiCl < O2 < Br2 < CH3OH

40. The solubility of a gas in a liquid depends on

_____.

A) temperature

B) pressure

C) nature of the gas

D) all of the above

42. The solubility of oxygen in water can be increased

by _____.

A) increase of temperature

B) decrease of pressure

C) decrease of temperature

D) increase of volume of O2

98. The best solvent for iodine is _____.

A) water

B) methanol, CH3OH

C) n-pentane, C5H12

D) ethanol, C2H5OH

99. The best solvent for KBr is _____.

A) methanol, CH3OH

B) n-hexane, C6H14

C) benzene, C6H6

D) chloroform, CHCl3

101. Which of the following statements is correct?

A) Hypertonic solutions cause blood cells to shrink

B) Hypertonic solutions cause blood cells to expand

C) Isotonic solutions cause blood cells to expand

D) Hypotonic solutions cause blood cells to shrink