Question 1

What types of forces exist between molecules of CO2?

Accepted Answer

A)  hydrogen bonding only. 
B)  hydrogen bonding and dispersion forces. 
C)  dipole-dipole forces only. 
D)  dipole-dipole and dispersion forces. 
E)  dispersion forces only. 
A)  hydrogen bonding only. 
B)  hydrogen bonding and dispersion forces. 
C)  dipole-dipole forces only. 
D)  dipole-dipole and dispersion forces. 
E)  dispersion forces only.

Question 2

Which of the following statements about the packing of monatomic solids with different unit cells is incorrect?

Accepted Answer

A)  The coordination number of atoms in hcp and fcc structures is 12. 
B)  The coordination number of atoms in simple cubic structures is 6. 
C)  The coordination number of atoms in bcc structures is 8. 
D)  A bcc structure has a higher packing efficiency than a simple cubic structure. 
E)  A bcc structure has a higher packing efficiency than a fcc structure. 
A)  The coordination number of atoms in hcp and fcc structures is 12. 
B)  The coordination number of atoms in simple cubic structures is 6. 
C)  The coordination number of atoms in bcc structures is 8. 
D)  A bcc structure has a higher packing efficiency than a simple cubic structure. 
E)  A bcc structure has a higher packing efficiency than a fcc structure.

Question 3

The phase diagram for xenon has a solid-liquid curve with a positive slope. Which of the following is true?

Accepted Answer

A)  Solid xenon has a higher density than liquid xenon. 
B)  Solid xenon has the same density as liquid xenon. 
C)  The phase diagram cannot be used to predict which phase of xenon is denser. 
D)  Freezing xenon is an endothermic process. 
E)  None of the above statements is true. 
A)  Solid xenon has a higher density than liquid xenon. 
B)  Solid xenon has the same density as liquid xenon. 
C)  The phase diagram cannot be used to predict which phase of xenon is denser. 
D)  Freezing xenon is an endothermic process. 
E)  None of the above statements is true.

Question 4

Which of the following statements about ceramics is incorrect?

Accepted Answer

A)  Silicon carbide has a diamond-like structure. 
B)  Boron nitride can exist in both diamond-like and graphite-like forms. 
C)  Silicon carbide can be prepared by direct reaction of silicon and carbon. 
D)  Superconducting ceramics present manufacturing difficulties owing to their brittleness. 
E)  Superconducting ceramic compounds usually incorporate cobalt in a key role. 
A)  Silicon carbide has a diamond-like structure. 
B)  Boron nitride can exist in both diamond-like and graphite-like forms. 
C)  Silicon carbide can be prepared by direct reaction of silicon and carbon. 
D)  Superconducting ceramics present manufacturing difficulties owing to their brittleness. 
E)  Superconducting ceramic compounds usually incorporate cobalt in a key role.

Question 5

List the three common classes of liquid crystals in order of decreasing degree of order.

Accepted Answer

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Question 6

A single water molecule can participate in at most two hydrogen bonds at any instant.

Accepted Answer

A) True 
 B)False

Question 7

The strongest intermolecular interactions between pentane (C5H12) molecules arise from

Accepted Answer

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

Question 8

The normal boiling point of ether is 307.8 K. Calculate the temperature at which its vapor pressure is exactly half of that at its normal boiling point. The heat of vaporization for ether is 26.69 kJ/mol.

Accepted Answer

A)  305 K 
B)  302 K 
C)  295 K 
D)  289 K 
E)  281 K 
A)  305 K 
B)  302 K 
C)  295 K 
D)  289 K 
E)  281 K

Question 9

The phase diagram of a substance shows the energy changes associated with changes of state.

Accepted Answer

A) True 
 B)False

Question 10

Which of the following should have the lowest boiling point?

Accepted Answer

A)  C5H12 
B)  C6H14 
C)  C8H18 
D)  C10H22 
E)  C12H26 
A)  C5H12 
B)  C6H14 
C)  C8H18 
D)  C10H22 
E)  C12H26

Question 11

A cubic unit cell has an edge length of 400. pm. The length of its body diagonal (internal diagonal) in pm is therefore

Accepted Answer

A)  512. 
B)  566. 
C)  631. 
D)  693. 
E)  724. 
A)  512. 
B)  566. 
C)  631. 
D)  693. 
E)  724.

Question 12

In metals, the conduction bands and valence bands of the molecular orbitals are separated by a large energy gap.

Accepted Answer

A) True 
 B)False

Question 13

In which of the following compounds will the molecules not form hydrogen bonds with each other?

Accepted Answer

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

Question 14

Comparing the energies of the following intermolecular forces on a kJ/mol basis, which would normally have the highest energy (i.e., be the strongest force)?

Accepted Answer

A)  ion-induced dipole 
B)  dipole-induced dipole 
C)  ion-dipole 
D)  dipole-dipole 
E)  dispersion 
A)  ion-induced dipole 
B)  dipole-induced dipole 
C)  ion-dipole 
D)  dipole-dipole 
E)  dispersion

Question 15

Which one of the following substances will have hydrogen bonds between molecules?

Accepted Answer

A)  (CH3)3N 
B)  CH3-O-CH3 
C)  CH3CH2-OH 
D)  CH3CH2-F 
E)  HI 
A)  (CH3)3N 
B)  CH3-O-CH3 
C)  CH3CH2-OH 
D)  CH3CH2-F 
E)  HI

Question 16

Ceramic superconductors often contain copper in unusual oxidation states.

Accepted Answer

A) True 
 B)False

Question 17

Which of the following should have the highest surface tension at a given temperature?

Accepted Answer

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

Question 18

The coordination number of sodium and chloride ions in the NaCl lattice, are, respectively:

Accepted Answer

A)  10 and 10 
B)  8 and 8 
C)  6 and 6 
D)  4 and 4 
E)  none of the above 
A)  10 and 10 
B)  8 and 8 
C)  6 and 6 
D)  4 and 4 
E)  none of the above

Question 19

Pentane, C5H12, boils at 35°C. Which of the following is true about kinetic energy, Ek, and potential energy, Ep, when liquid pentane at 35°C is compared with pentane vapor at 35°C?

Accepted Answer

A)  Ek(g) k(l); Ep(g) F1F1F1S1F1F1F10 Ep(l) 
B)  Ek(g) > Ek(l); Ep(g) F1F1F1S1F1F1F10 Ep(l) 
C)  Ep(g) p(l); Ek(g) F1F1F1S1F1F1F10 Ek(l) 
D)  Ep(g) > Ep(l); Ek(g) F1F1F1S1F1F1F10 Ek(l) 
E)  Ep(g) F1F1F1S1F1F1F10 Ep(l); Ek(g) F1F1F1S1F1F1F10 Ek(l) 
A)  Ek(g) k(l); Ep(g) F1F1F1S1F1F1F10 Ep(l) 
B)  Ek(g) > Ek(l); Ep(g) F1F1F1S1F1F1F10 Ep(l) 
C)  Ep(g) p(l); Ek(g) F1F1F1S1F1F1F10 Ek(l) 
D)  Ep(g) > Ep(l); Ek(g) F1F1F1S1F1F1F10 Ek(l) 
E)  Ep(g) F1F1F1S1F1F1F10 Ep(l); Ek(g) F1F1F1S1F1F1F10 Ek(l)

Question 20

Which of the following pairs of substances is arranged so that the one with higher viscosity is listed first?

Accepted Answer

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

Exam 12: Intermolecular Forces: Liquids, Solids, and Phase Changes

What types of forces exist between molecules of CO2?

Which of the following statements about the packing of monatomic solids with different unit cells is incorrect?

The phase diagram for xenon has a solid-liquid curve with a positive slope. Which of the following is true?

Which of the following statements about ceramics is incorrect?

List the three common classes of liquid crystals in order of decreasing degree of order.

A single water molecule can participate in at most two hydrogen bonds at any instant.

The strongest intermolecular interactions between pentane (C5H12) molecules arise from

The normal boiling point of ether is 307.8 K. Calculate the temperature at which its vapor pressure is exactly half of that at its normal boiling point. The heat of vaporization for ether is 26.69 kJ/mol.

The phase diagram of a substance shows the energy changes associated with changes of state.

Which of the following should have the lowest boiling point?

A cubic unit cell has an edge length of 400. pm. The length of its body diagonal (internal diagonal) in pm is therefore

In metals, the conduction bands and valence bands of the molecular orbitals are separated by a large energy gap.

In which of the following compounds will the molecules not form hydrogen bonds with each other?

Comparing the energies of the following intermolecular forces on a kJ/mol basis, which would normally have the highest energy (i.e., be the strongest force)?

Which one of the following substances will have hydrogen bonds between molecules?

Ceramic superconductors often contain copper in unusual oxidation states.

Which of the following should have the highest surface tension at a given temperature?

The coordination number of sodium and chloride ions in the NaCl lattice, are, respectively:

Pentane, C5H12, boils at 35°C. Which of the following is true about kinetic energy, Ek, and potential energy, Ep, when liquid pentane at 35°C is compared with pentane vapor at 35°C?

Which of the following pairs of substances is arranged so that the one with higher viscosity is listed first?

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

The Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main Group Elements: Bonding, Structure, and Reactivity

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

What types of forces exist between molecules of CO₂?

The strongest intermolecular interactions between pentane (C₅H₁₂) molecules arise from

Pentane, C₅H₁₂, boils at 35°C. Which of the following is true about kinetic energy, E_k, and potential energy, E_p, when liquid pentane at 35°C is compared with pentane vapor at 35°C?