Question 1

Select the compound with the lowest (i.e., least negative) lattice energy.

Accepted Answer

A)  CsBr(s) 
B)  NaCl(s) 
C)  SrO(s) 
D)  CaO(s) 
E)  KBr(s) 
A)  CsBr(s) 
B)  NaCl(s) 
C)  SrO(s) 
D)  CaO(s) 
E)  KBr(s) A

Question 2

Calculate the lattice energy of magnesium sulfide from the data given below. Mg(s) $\rightarrow$ Mg(g) ?H$\degree$= 148 kJ/mol
Mg(g) $\rightarrow$ Mg2+(g) + 2e¯ ?H$\degree$ = 2186 kJ/mol
S8(s) $\rightarrow$ 8S(g) ?H$\degree$ = 2232 kJ/mol
S(g) + 2e¯ $\rightarrow$S2¯(g) ?H$\degree$= 450 kJ/mol
8Mg(s) + S8(s) $\rightarrow$8MgS(s) ?H$\degree$ = -2744 kJ/mol
Mg2+(g) + S2¯(g) $\rightarrow$ MgS(s) ?H$\degree$lattice = ?

Accepted Answer

A)  -3406 kJ/mol 
B)  -2720. kJ/mol 
C)  2720. kJ/mol 
D)  3406 kJ/mol 
E)  None of these choices is correct. 
A)  -3406 kJ/mol 
B)  -2720. kJ/mol 
C)  2720. kJ/mol 
D)  3406 kJ/mol 
E)  None of these choices is correct. A

Question 3

Select the element whose Lewis symbol is correct.

Accepted Answer

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

Question 4

Based on electronegativity trends in the periodic table, predict which of the following compounds will have the greatest % ionic character in its bonds.

Accepted Answer

A)  H2O 
B)  LiI 
C)  CaO 
D)  RbF 
E)  HCl 
A)  H2O 
B)  LiI 
C)  CaO 
D)  RbF 
E)  HCl

Question 5

The lattice energy for ionic crystals increases as the charge on the ions _____________ and the size of the ions __________________ .

Accepted Answer

A)  increases, increases 
B)  increases, decreases 
C)  decreases, increases 
D)  decreases, decreases 
E)  None of these choices is generally correct. 
A)  increases, increases 
B)  increases, decreases 
C)  decreases, increases 
D)  decreases, decreases 
E)  None of these choices is generally correct.

Question 6

In covalent bond formation, the potential energy reaches a maximum when the internuclear distance is equal to the bond length.

Accepted Answer

A) True 
 B)False

Question 7

Which of the following period 3 chlorides would be expected to have the highest melting point?

Accepted Answer

A)  MgCl2 
B)  AlCl3 
C)  SiCl4 
D)  PCl3 
E)  SCl2 
A)  MgCl2 
B)  AlCl3 
C)  SiCl4 
D)  PCl3 
E)  SCl2

Question 8

In not more than three sentences, describe the key features of bonding in solid aluminum.

Accepted Answer

This is metallic bonding. The aluminum a

Question 9

Electronegativities on Pauling's scale are calculated from ionization energies and electron affinities.

Accepted Answer

A) True 
 B)False

Question 10

Covalent bonding typically occurs when a ______________ bonds with a ______________.

Accepted Answer

non-metal;

Question 11

Arrange calcium, rubidium, sulfur, and arsenic in order of decreasing electronegativity.

Accepted Answer

A)  S > As > Rb > Ca 
B)  S > As > Ca > Rb 
C)  As > S > Rb > Ca 
D)  As > S > Ca > Rb 
E)  None of these choices is correct. 
A)  S > As > Rb > Ca 
B)  S > As > Ca > Rb 
C)  As > S > Rb > Ca 
D)  As > S > Ca > Rb 
E)  None of these choices is correct.

Question 12

Which of the following compounds displays the greatest ionic character in its bonds?

Accepted Answer

A)  NO2 
B)  CO2 
C)  H2O 
D)  HF 
E)  NH3 
A)  NO2 
B)  CO2 
C)  H2O 
D)  HF 
E)  NH3

Question 13

In which of these substances are the atoms held together by metallic bonding?

Accepted Answer

A)  CO2 
B)  Si 
C)  Br2 
D)  S8 
E)  Cr 
A)  CO2 
B)  Si 
C)  Br2 
D)  S8 
E)  Cr

Question 14

Which of the following is an ionic compound?

Accepted Answer

A)  H2S 
B)  NH3 
C)  I2 
D)  KI 
E)  CCl4 
A)  H2S 
B)  NH3 
C)  I2 
D)  KI 
E)  CCl4

Question 15

Arrange the following bonds in order of increasing bond strength.

Accepted Answer

A)  
C   I < C
  Br < C
  Cl < C
  F 
B)  
C   F < C
  Cl < C
  Br < C
  I 
C)  
C   Br < C
  I < C
  Cl < C
  F 
D)  
C   I < C
  Br < C
  F< C
  Cl 
E)  None of these choices is correct. 
A)  
C   I < C
  Br < C
  Cl < C
  F 
B)  
C   F < C
  Cl < C
  Br < C
  I 
C)  
C   Br < C
  I < C
  Cl < C
  F 
D)  
C   I < C
  Br < C
  F< C
  Cl 
E)  None of these choices is correct.

Question 16

Which of the following elements is the most electronegative?

Accepted Answer

A)  Ne 
B)  Rb 
C)  P 
D)  I 
E)  Cl 
A)  Ne 
B)  Rb 
C)  P 
D)  I 
E)  Cl

Question 17

Describe in brief how electronegativity values can be used to predict the percent ionic character of a bond between two atoms.

Accepted Answer

Take the electronegativity difference (∆

Question 18

In which of these substances are the atoms held together by polar covalent bonding?

Accepted Answer

A)  SrCl2 
B)  CsCl 
C)  ClF 
D)  TiF2 
E)  S8 
A)  SrCl2 
B)  CsCl 
C)  ClF 
D)  TiF2 
E)  S8

Question 19

A Born-Haber cycle applied to the formation reaction of an ionic solid

Accepted Answer

A)  is normally used to calculate ionization energy. 
B)  is normally used to calculate electron affinity. 
C)  is normally used to calculate bond energy. 
D)  is normally used to determine the overall enthalpy change. 
E)  is an application of Hess's Law. 
A)  is normally used to calculate ionization energy. 
B)  is normally used to calculate electron affinity. 
C)  is normally used to calculate bond energy. 
D)  is normally used to determine the overall enthalpy change. 
E)  is an application of Hess's Law.

Question 20

Analysis of an unknown substance showed that it has a high boiling point and is brittle. It is an insulator as a solid but conducts electricity when melted. Which of the following substances would have those characteristics?

Accepted Answer

A)  HCl 
B)  Al 
C)  KBr 
D)  SiF4 
E)  I2 
A)  HCl 
B)  Al 
C)  KBr 
D)  SiF4 
E)  I2

Exam 9: Models of Chemical Bonding

Select the compound with the lowest (i.e., least negative) lattice energy.

Select the element whose Lewis symbol is correct.

Based on electronegativity trends in the periodic table, predict which of the following compounds will have the greatest % ionic character in its bonds.

The lattice energy for ionic crystals increases as the charge on the ions _____________ and the size of the ions __________________ .

In covalent bond formation, the potential energy reaches a maximum when the internuclear distance is equal to the bond length.

Which of the following period 3 chlorides would be expected to have the highest melting point?

In not more than three sentences, describe the key features of bonding in solid aluminum.

Electronegativities on Pauling's scale are calculated from ionization energies and electron affinities.

Covalent bonding typically occurs when a ______________ bonds with a ______________.

Arrange calcium, rubidium, sulfur, and arsenic in order of decreasing electronegativity.

Which of the following compounds displays the greatest ionic character in its bonds?

In which of these substances are the atoms held together by metallic bonding?

Which of the following is an ionic compound?

Arrange the following bonds in order of increasing bond strength.

Which of the following elements is the most electronegative?

Describe in brief how electronegativity values can be used to predict the percent ionic character of a bond between two atoms.

In which of these substances are the atoms held together by polar covalent bonding?

A Born-Haber cycle applied to the formation reaction of an ionic solid

Analysis of an unknown substance showed that it has a high boiling point and is brittle. It is an insulator as a solid but conducts electricity when melted. Which of the following substances would have those characteristics?

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three 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

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

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

The lattice energy for ionic crystals increases as the charge on the ions _ and the size of the ions ______ .

Covalent bonding typically occurs when a bonds with a .