Question 1

Which of the following substances would you predict to have the highest ΔHvap?

Accepted Answer

A)  Xe 
B)  C6H6 
C)  SiF4 
D)  F2 
E)  N2 
A)  Xe 
B)  C6H6 
C)  SiF4 
D)  F2 
E)  N2

Question 2

Choose the substance with the lowest boiling point.

Accepted Answer

A)  H2S 
B)  NBr3 
C)  O2 
D)  CI2H2 
E)  H2O2 
A)  H2S 
B)  NBr3 
C)  O2 
D)  CI2H2 
E)  H2O2

Question 3

Give the term for the temperature at which the gas and liquid phases form a supercritical fluid.

Accepted Answer

A)  absolute temperature 
B)  definite temperature 
C)  fluid temperature 
D)  critical temperature 
E)  solid temperature 
A)  absolute temperature 
B)  definite temperature 
C)  fluid temperature 
D)  critical temperature 
E)  solid temperature

Question 4

Place the following substances in order of increasing boiling point. CH3CH2OH He CH3OCH3

Accepted Answer

A)  He 3OCH3 3CH2OH 
B)  CH3CH2OH 3OCH3 
C)  CH3CH2OH 3OCH3 3OCH3 3CH2OH 
E)  He 3CH2OH 3OCH3  
A)  He 3OCH3 3CH2OH 
B)  CH3CH2OH 3OCH3 
C)  CH3CH2OH 3OCH3 3OCH3 3CH2OH 
E)  He 3CH2OH 3OCH3

Question 5

Assign the appropriate labels to the phase diagram shown below.

Accepted Answer

A)  A = liquid, B = solid, C = gas, D = critical point 
B)  A = gas, B = solid, C = liquid, D = triple point 
C)  A = gas, B = liquid, C = solid, D = critical point 
D)  A = solid, B = gas, C = liquid, D = triple point 
E)  A = liquid, B = gas, C = solid, D = critical point 
A)  A = liquid, B = solid, C = gas, D = critical point 
B)  A = gas, B = solid, C = liquid, D = triple point 
C)  A = gas, B = liquid, C = solid, D = critical point 
D)  A = solid, B = gas, C = liquid, D = triple point 
E)  A = liquid, B = gas, C = solid, D = critical point

Question 6

Define sublimation.

Accepted Answer

A)  the phase transition from solid to gas 
B)  the phase transition from gas to solid 
C)  the phase transition from gas to liquid 
D)  the phase transition from liquid to gas 
E)  the phase transition from liquid to solid 
A)  the phase transition from solid to gas 
B)  the phase transition from gas to solid 
C)  the phase transition from gas to liquid 
D)  the phase transition from liquid to gas 
E)  the phase transition from liquid to solid

Question 7

Which of the following statements is TRUE?

Accepted Answer

A)  Intermolecular forces are generally stronger than bonding forces. 
B)  The potential energy of molecules decrease as they get closer to one another. 
C)  Energy is given off when the attraction between two molecules is broken. 
D)  Increasing the pressure on a solid usually causes it to become a liquid. 
E)  None of the above are true. 
A)  Intermolecular forces are generally stronger than bonding forces. 
B)  The potential energy of molecules decrease as they get closer to one another. 
C)  Energy is given off when the attraction between two molecules is broken. 
D)  Increasing the pressure on a solid usually causes it to become a liquid. 
E)  None of the above are true.

Question 8

Choose the substance with the highest boiling point.

Accepted Answer

A)  CH4 
B)  K I 
C)  CS2 
D)  HF 
E)  I2 
A)  CH4 
B)  K I 
C)  CS2 
D)  HF 
E)  I2

Question 9

Which of the following substances would you predict to have the highest ΔHvap?

Accepted Answer

A)  CH3Cl 
B)  HCl 
C)  HOCH2CH2OH 
D)  CH3CH2OH 
E)  CH3CH2CH2CH3 
A)  CH3Cl 
B)  HCl 
C)  HOCH2CH2OH 
D)  CH3CH2OH 
E)  CH3CH2CH2CH3

Question 10

Why is water an extraordinary substance?

Accepted Answer

A)  Water has a low molar mass, yet it is a liquid at room temperature. 
B)  Water is the main solvent within living organisms. 
C)  Water has an exceptionally high specific heat capacity. 
D)  Water has strong hydrogen bonding. 
E)  All of the above 
A)  Water has a low molar mass, yet it is a liquid at room temperature. 
B)  Water is the main solvent within living organisms. 
C)  Water has an exceptionally high specific heat capacity. 
D)  Water has strong hydrogen bonding. 
E)  All of the above

Question 11

Give the change in condition to go from a liquid to a gas.

Accepted Answer

A)  increase heat or reduce pressure 
B)  increase heat or increase pressure 
C)  cool or reduce pressure 
D)  cool or increase pressure 
E)  none of the above 
A)  increase heat or reduce pressure 
B)  increase heat or increase pressure 
C)  cool or reduce pressure 
D)  cool or increase pressure 
E)  none of the above

Question 12

Calculate the energy that is required to change 50.0 g ice at -30.0°C to a liquid at 73.0°C.The heat of fusion = 333 J/g,the heat of vaporization = 2256 J/g,and the specific heat capacities of ice = 2.06 J /gK and liquid water = 4.184 J /gK.

Accepted Answer

A)  3.50 × 104 J 
B)  2.14 × 104 J 
C)  1.31 × 105 J 
D)  6.59 × 103 J 
E)  1.66 × 104 J 
A)  3.50 × 104 J 
B)  2.14 × 104 J 
C)  1.31 × 105 J 
D)  6.59 × 103 J 
E)  1.66 × 104 J

Question 13

How much energy is required to heat 87.1 g acetone (molar mass=58.08 g/mol)from a solid at -154.0°C to a liquid at -42.0°C? The following physical data may be useful.
ΔHfus = 7.27 kJ/mol
Cliq = 2.16 J/g°C
Cgas = 1.29 J/g°C
Csol = 1.65 J/g°C
Tmelting = -95.0°C

Accepted Answer

A)  8.48 kJ 
B)  18.5 kJ 
C)  32.2 kJ 
D)  29.4 kJ 
E)  9.97 kJ 
A)  8.48 kJ 
B)  18.5 kJ 
C)  32.2 kJ 
D)  29.4 kJ 
E)  9.97 kJ

Question 14

The heat required to melt 1 mol of a solid is known as the

Accepted Answer

A)  melting point. 
B)  heat of fusion. 
C)  freezing point. 
D)  heat of vaporization. 
E)  critical point. 
A)  melting point. 
B)  heat of fusion. 
C)  freezing point. 
D)  heat of vaporization. 
E)  critical point.

Question 15

Place the following substances in order of decreasing boiling point. H2O N2 CO

Accepted Answer

A)  CO > H2O > N2 
B)  N2 > CO > H2O 
C)  H2O > CO > N2 
D)  CO > N2 > H2O 
E)  N2 > H2O > CO 
A)  CO > H2O > N2 
B)  N2 > CO > H2O 
C)  H2O > CO > N2 
D)  CO > N2 > H2O 
E)  N2 > H2O > CO

Question 16

Choose the molecule or compound that exhibits dipole-dipole forces as its strongest intermolecular force.

Accepted Answer

A)  H2 
B)  SO2 
C)  NH3 
D)  CF4 
E)  BCl3 
A)  H2 
B)  SO2 
C)  NH3 
D)  CF4 
E)  BCl3

Question 17

Choose the substance with the lowest vapor pressure at a given temperature.

Accepted Answer

A)  CO2 
B)  Ca I2 
C)  BF3 
D)  Ar 
E)  PF5 
A)  CO2 
B)  Ca I2 
C)  BF3 
D)  Ar 
E)  PF5

Question 18

Ethyl chloride,C2H5Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes; its heat of vaporization is 26.4 kJ/mol.How much heat could be removed by 20.0 g of ethyl chloride?

Accepted Answer

A)  8.18 kJ 
B)  341 kJ 
C)  528 kJ 
D)  3410 kJ 
A)  8.18 kJ 
B)  341 kJ 
C)  528 kJ 
D)  3410 kJ

Question 19

Determine the vapor pressure (in mm Hg)of a substance at 29°C,whose normal boiling point is 76°C and has a ΔHvap of 38.7 kJ/mol.

Accepted Answer

A)  80 mm Hg 
B)  13 mm Hg 
C)  21 mm Hg 
D)  48 mm Hg 
E)  96 mm Hg 
A)  80 mm Hg 
B)  13 mm Hg 
C)  21 mm Hg 
D)  48 mm Hg 
E)  96 mm Hg

Question 20

Choose the compound that exhibits hydrogen bonding as its strongest intermolecular force.

Accepted Answer

A)  SBr2 
B)  C2H6 
C)  CH3OH 
D)  CH2Br2 
E)  None of the above compounds exhibit hydrogen bonding. 
A)  SBr2 
B)  C2H6 
C)  CH3OH 
D)  CH2Br2 
E)  None of the above compounds exhibit hydrogen bonding.

Exam 12: Liquids, Solids, and Intermolecular Forces

Which of the following substances would you predict to have the highest ΔHvap?

Choose the substance with the lowest boiling point.

Give the term for the temperature at which the gas and liquid phases form a supercritical fluid.

Place the following substances in order of increasing boiling point. CH3CH2OH He CH3OCH3

Assign the appropriate labels to the phase diagram shown below.

Define sublimation.

Which of the following statements is TRUE?

Choose the substance with the highest boiling point.

Which of the following substances would you predict to have the highest ΔHvap?

Why is water an extraordinary substance?

Give the change in condition to go from a liquid to a gas.

Calculate the energy that is required to change 50.0 g ice at -30.0°C to a liquid at 73.0°C.The heat of fusion = 333 J/g,the heat of vaporization = 2256 J/g,and the specific heat capacities of ice = 2.06 J /gK and liquid water = 4.184 J /gK.

How much energy is required to heat 87.1 g acetone (molar mass=58.08 g/mol)from a solid at -154.0°C to a liquid at -42.0°C? The following physical data may be useful. ΔHfus = 7.27 kJ/mol Cliq = 2.16 J/g°C Cgas = 1.29 J/g°C Csol = 1.65 J/g°C Tmelting = -95.0°C

The heat required to melt 1 mol of a solid is known as the

Place the following substances in order of decreasing boiling point. H2O N2 CO

Choose the molecule or compound that exhibits dipole-dipole forces as its strongest intermolecular force.

Choose the substance with the lowest vapor pressure at a given temperature.

Ethyl chloride,C2H5Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes; its heat of vaporization is 26.4 kJ/mol.How much heat could be removed by 20.0 g of ethyl chloride?

Determine the vapor pressure (in mm Hg)of a substance at 29°C,whose normal boiling point is 76°C and has a ΔHvap of 38.7 kJ/mol.

Choose the compound that exhibits hydrogen bonding as its strongest intermolecular force.

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Crystalline Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

Which of the following substances would you predict to have the highest ΔH_vap?

Place the following substances in order of increasing boiling point. CH₃CH₂OH He CH₃OCH₃

Which of the following substances would you predict to have the highest ΔH_vap?

How much energy is required to heat 87.1 g acetone (molar mass=58.08 g/mol)from a solid at -154.0°C to a liquid at -42.0°C? The following physical data may be useful. ΔH_fus = 7.27 kJ/mol C_liq = 2.16 J/g°C C_gas= 1.29 J/g°C C_sol = 1.65 J/g°C T_melting= -95.0°C

Place the following substances in order of decreasing boiling point. H₂O N₂ CO

Ethyl chloride,C₂H₅Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes; its heat of vaporization is 26.4 kJ/mol.How much heat could be removed by 20.0 g of ethyl chloride?

Determine the vapor pressure (in mm Hg)of a substance at 29°C,whose normal boiling point is 76°C and has a ΔH_vapof 38.7 kJ/mol.