Question 1

What is the edge length of a face-centred cubic unit cell made up of atoms having a radius of 128 pm?

Accepted Answer

A)  181 pm 
B)  362 pm 
C)  512 pm 
D)  1020 pm 
A)  181 pm 
B)  362 pm 
C)  512 pm 
D)  1020 pm

Question 2

Why do O, F and N, when bonded to H, form such strong intermolecular attractions to neighbouring molecules? Make sure to be specific.

Accepted Answer

Oxygen, fluorine, and nitrogen are all v

Question 3

Which of the following compounds has the highest boiling point?

Accepted Answer

A)  H2O 
B)  H Cl 
C)  H2S  
D)  N H3 
A)  H2O 
B)  H Cl 
C)  H2S  
D)  N H3

Question 4

The melting point of water is ________.

Accepted Answer

A)  0 °C 
B)  32 °C 
C)  212 °C 
D)  100 °C 
E)  273 °C 
A)  0 °C 
B)  32 °C 
C)  212 °C 
D)  100 °C 
E)  273 °C

Question 5

How much heat is released when 105 g of steam at 100.0 °C is cooled to ice at -15.0 °C? The enthalpy of vaporization of water is 40.67 kJ mol-1, the enthalpy of fusion for water is 6.01 kJ mol-1, the molar heat capacity of liquid water is 75.4 J mol-1 °C-1, and the molar heat capacity of ice is 36.4 J mol-1 °C-1.

Accepted Answer

A)  54.8 kJ 
B)  273 kJ 
C)  319 kJ 
D)  347 kJ 
A)  54.8 kJ 
B)  273 kJ 
C)  319 kJ 
D)  347 kJ

Question 6

What is the packing efficiency in simple cubic unit cells?

Accepted Answer

A)  74% 
B)  86% 
C)  68% 
D)  52% 
E)  24% 
A)  74% 
B)  86% 
C)  68% 
D)  52% 
E)  24%

Question 7

Why does the temperature of a substance stay constant during a phase change such as vaporization?

Accepted Answer

The energy added to the substance is not

Question 8

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

Accepted Answer

A)  CO2 
B)  BeCl2 
C)  BF3 
D)  He 
E)  PF5 
A)  CO2 
B)  BeCl2 
C)  BF3 
D)  He 
E)  PF5

Question 9

Place the following compounds in order of increasing strength of intermolecular forces. CH4 CH3CH2CH3 CH3CH3

Accepted Answer

A)  CH3CH2CH3 4 3CH3 
B)  CH3CH2CH3 3CH3 4 
C)  CH3CH3 4 3CH2CH3 
D)  CH4 3CH2CH3 3CH3 
E)  CH4 3CH3 3CH2CH3 
A)  CH3CH2CH3 4 3CH3 
B)  CH3CH2CH3 3CH3 4 
C)  CH3CH3 4 3CH2CH3 
D)  CH4 3CH2CH3 3CH3 
E)  CH4 3CH3 3CH2CH3

Question 10

Which one of the following has a definite shape and volume?

Accepted Answer

A)  gas 
B)  liquid 
C)  solid 
D)  none of the above 
A)  gas 
B)  liquid 
C)  solid 
D)  none of the above

Question 11

Consider the phase diagram shown. Choose the statement below that is TRUE.

Accepted Answer

A)  The triple point of this substance occurs at a temperature of 31 °C. 
B)  At 10 bar of pressure, there is no temperature where the liquid phase of this substance would exist. 
C)  The solid phase of this substance is higher in density than the liquid phase. 
D)  The line separating the solid and liquid phases represents the ΔvapH. 
A)  The triple point of this substance occurs at a temperature of 31 °C. 
B)  At 10 bar of pressure, there is no temperature where the liquid phase of this substance would exist. 
C)  The solid phase of this substance is higher in density than the liquid phase. 
D)  The line separating the solid and liquid phases represents the ΔvapH.

Question 12

Identify the characteristics of a liquid.

Accepted Answer

A)  indefinite shape and volume 
B)  indefinite shape, but definite volume 
C)  definite shape and volume 
D)  definite shape and indefinite volume 
A)  indefinite shape and volume 
B)  indefinite shape, but definite volume 
C)  definite shape and volume 
D)  definite shape and indefinite volume

Question 13

Determine ΔvapH for a compound that has a measured vapour pressure of 32.40 mbar at 273 K and 180.0 mbar at 325 K.

Accepted Answer

A)  41 kJ mol-1 
B)  79 kJ mol-1 
C)  24 kJ mol-1 
D)  13 kJ mol-1 
E)  34 kJ mol-1 
A)  41 kJ mol-1 
B)  79 kJ mol-1 
C)  24 kJ mol-1 
D)  13 kJ mol-1 
E)  34 kJ mol-1

Question 14

Which of the following forms a molecular solid?

Accepted Answer

A)  NH4NO3 
B)  C6H4Cl2 
C)  SiO2 
D)  copper 
A)  NH4NO3 
B)  C6H4Cl2 
C)  SiO2 
D)  copper

Question 15

Which of the following statements is FALSE?

Accepted Answer

A)  The rate of vaporization increases with increasing surface area. 
B)  The rate of vaporization increases with decreasing strength of intermolecular forces. 
C)  The rate of vaporization increases with increasing temperature. 
D)  Molecules with hydrogen bonding are more volatile than compounds with dipole-dipole forces. 
A)  The rate of vaporization increases with increasing surface area. 
B)  The rate of vaporization increases with decreasing strength of intermolecular forces. 
C)  The rate of vaporization increases with increasing temperature. 
D)  Molecules with hydrogen bonding are more volatile than compounds with dipole-dipole forces.

Question 16

Which of the following substances should have the highest melting point?

Accepted Answer

A)  CO2 
B)  SrS 
C)  Xe 
D)  F2 
E)  MgO 
A)  CO2 
B)  SrS 
C)  Xe 
D)  F2 
E)  MgO

Question 17

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 18

Which is expected to have the largest dispersion forces?

Accepted Answer

A)  C2H4 
B)  C8H16 
C)  Cl2 
D)  N2H4 
A)  C2H4 
B)  C8H16 
C)  Cl2 
D)  N2H4

Question 19

Choose the substance with the highest vapour pressure at a given temperature.

Accepted Answer

A)  SiS2 
B)  RbCl 
C)  CH3SCH3 
D)  BF3 
E)  SbH3 
A)  SiS2 
B)  RbCl 
C)  CH3SCH3 
D)  BF3 
E)  SbH3

Question 20

Place the following substances in order of increasing vapour pressure at a given temperature. NF3 NH3 BCl3

Accepted Answer

A)  NH3 3 3 
B)  NF3 3 3 
C)  BCl3 3 3 
D)  NH3 3 3 
E)  BCl3 3 3 
A)  NH3 3 3 
B)  NF3 3 3 
C)  BCl3 3 3 
D)  NH3 3 3 
E)  BCl3 3 3

Exam 11: Liquids, Solids, and Intermolecular Forces

What is the edge length of a face-centred cubic unit cell made up of atoms having a radius of 128 pm?

Why do O, F and N, when bonded to H, form such strong intermolecular attractions to neighbouring molecules? Make sure to be specific.

Which of the following compounds has the highest boiling point?

The melting point of water is ________.

What is the packing efficiency in simple cubic unit cells?

Why does the temperature of a substance stay constant during a phase change such as vaporization?

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

Place the following compounds in order of increasing strength of intermolecular forces. CH4 CH3CH2CH3 CH3CH3

Which one of the following has a definite shape and volume?

Consider the phase diagram shown. Choose the statement below that is TRUE.

Identify the characteristics of a liquid.

Determine ΔvapH for a compound that has a measured vapour pressure of 32.40 mbar at 273 K and 180.0 mbar at 325 K.

Which of the following forms a molecular solid?

Which of the following statements is FALSE?

Which of the following substances should have the highest melting point?

Define sublimation.

Which is expected to have the largest dispersion forces?

Choose the substance with the highest vapour pressure at a given temperature.

Place the following substances in order of increasing vapour pressure at a given temperature. NF3 NH3 BCl3

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Chemical Reactions and Stoichiometry

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry Ii: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallurgy

Transition Metals and Coordination Compounds

Filters

Place the following compounds in order of increasing strength of intermolecular forces. CH₄ CH₃CH₂CH₃ CH₃CH₃

Determine Δ_vapH for a compound that has a measured vapour pressure of 32.40 mbar at 273 K and 180.0 mbar at 325 K.

Place the following substances in order of increasing vapour pressure at a given temperature. NF₃ NH₃BCl₃