Question 1

The compound Al(ClO3)3 shows only ionic bonding.

Accepted Answer

A) True 
 B)False

Question 2

What is the total number of lone pairs in the best Lewis structure for SOF4 that exceeds the octet rule (S is the central atom)

Accepted Answer

A)  0 
B)  2 
C)  14 
D)  16 
E)  18 
A)  0 
B)  2 
C)  14 
D)  16 
E)  18

Question 3

A Lewis structure of boron trifluoride is shown here. How many valence electrons are shown directly around the B atom

Accepted Answer

A)  Eight 
B)  Six 
C)  Twenty-four 
D)  None 
E)  None of the above 
A)  Eight 
B)  Six 
C)  Twenty-four 
D)  None 
E)  None of the above

Question 4

Which one of these polar covalent bonds would have the greatest percent ionic character

Accepted Answer

A)  H - Br 
B)  H - Cl 
C)  H - F 
D)  H - I 
A)  H - Br 
B)  H - Cl 
C)  H - F 
D)  H - I

Question 5

Assuming the octet rule is obeyed, how many covalent bonds will a carbon atom form to give a formal charge of zero

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  3 
E)  4 
A)  0 
B)  1 
C)  2 
D)  3 
E)  4

Question 6

The Lewis structure shown here is correct for ammonia (nitrogen trihydride).

Accepted Answer

A) True 
 B)False

Question 7

Which of the following ionic solids would have the largest lattice energy

Accepted Answer

A)  SrO 
B)  NaF 
C)  CaBr2 
D)  CsI 
E)  BaSO4 
A)  SrO 
B)  NaF 
C)  CaBr2 
D)  CsI 
E)  BaSO4

Question 8

The properties and chemical reactivity of a molecule is best explained by analyzing all possible resonance structures for that molecule.

Accepted Answer

A) True 
 B)False

Question 9

Estimate the enthalpy change for the reaction 2CO + O2 $\rarr$ 2CO2 given the following bond energies.
BE(C$\equiv$O) = 1074 kJ/mol 
BE(O=O) = 499 kJ/mol
BE(C=O) = 802 kJ/mol

Accepted Answer

A)  +2380 kJ/mol 
B)  +1949 kJ/mol 
C)  +744 kJ/mol 
D)  -561 kJ/mol 
E)  -744 kJ/mol 
A)  +2380 kJ/mol 
B)  +1949 kJ/mol 
C)  +744 kJ/mol 
D)  -561 kJ/mol 
E)  -744 kJ/mol

Question 10

What is the formal charge on the singly bonded oxygens in the Lewis structure for the carbonate ion

Accepted Answer

A)  -2 
B)  -1 
C)  0 
D)  +1 
E)  +2 
A)  -2 
B)  -1 
C)  0 
D)  +1 
E)  +2

Question 11

The formal charge on the bromine atom in BrO3- drawn with three single bonds is

Accepted Answer

A)  -2. 
B)  -1. 
C)  0. 
D)  +1. 
E)  +2. 
A)  -2. 
B)  -1. 
C)  0. 
D)  +1. 
E)  +2.

Question 12

A nonpolar covalent bond (i.e., pure covalent) would form in which one of the following pairs of atoms

Accepted Answer

A)  Na - Cl 
B)  H - Cl 
C)  Li - Br 
D)  Se - Br 
E)  Br - Br 
A)  Na - Cl 
B)  H - Cl 
C)  Li - Br 
D)  Se - Br 
E)  Br - Br

Question 13

What is the formal charge on phosphorus in a Lewis structure for the phosphate ion that satisfies the octet rule

Accepted Answer

A)  -2 
B)  -1 
C)  0 
D)  +1 
E)  +2 
A)  -2 
B)  -1 
C)  0 
D)  +1 
E)  +2

Question 14

Which of the following solids would have the lowest melting point

Accepted Answer

A)  KI 
B)  KBr 
C)  KCl 
D)  KF 
A)  KI 
B)  KBr 
C)  KCl 
D)  KF

Question 15

Which one of the following molecules has an atom with an expanded octet

Accepted Answer

A)  HCl 
B)  AsCl5 
C)  ICl 
D)  NCl3 
E)  Cl2 
A)  HCl 
B)  AsCl5 
C)  ICl 
D)  NCl3 
E)  Cl2

Question 16

Define electronegativity:

Accepted Answer

A)  an atoms ability to attract electrons that are shared in a chemical bond 
B)  an atoms ability to form an ionic bond with another atom 
C)  an atoms ability to donate valence electrons to another atom 
D)  an atoms ability to form a cation 
E)  an atoms ability to form double and triple bonds 
A)  an atoms ability to attract electrons that are shared in a chemical bond 
B)  an atoms ability to form an ionic bond with another atom 
C)  an atoms ability to donate valence electrons to another atom 
D)  an atoms ability to form a cation 
E)  an atoms ability to form double and triple bonds

Question 17

Which one of the following is most likely to be an ionic compound

Accepted Answer

A)  CaCl2 
B)  CO2 
C)  CS2 
D)  SO2 
E)  OF2 
A)  CaCl2 
B)  CO2 
C)  CS2 
D)  SO2 
E)  OF2

Question 18

Use the Born-Haber cycle to calculate the lattice energy of KCl(s) given the following data: $\Delta$H(sublimation) K = 79.2 kJ/mol
I1 (K) = 418.7 kJ/mol
Bond energy (Cl-Cl) = 242.8 kJ/mol
EA (Cl) = 348 kJ/mol
$\Delta{H}^{\circ}_f$ (KCl(s)) = -435.7 kJ/mol

Accepted Answer

A)  -165 kJ/mol 
B)  288 kJ/mol 
C)  629 kJ/mol 
D)  707 kJ/mol 
E)  828 kJ/mol 
A)  -165 kJ/mol 
B)  288 kJ/mol 
C)  629 kJ/mol 
D)  707 kJ/mol 
E)  828 kJ/mol

Question 19

Which of the following is a useful guideline for the application of formal charges in neutral molecules

Accepted Answer

A)  A Lewis structure in which there are no formal charges is preferred. 
B)  Lewis structures with large formal charges are preferred. 
C)  The preferred Lewis structure is one in which positive formal charges are on the most electronegative atoms. 
A)  A Lewis structure in which there are no formal charges is preferred. 
B)  Lewis structures with large formal charges are preferred. 
C)  The preferred Lewis structure is one in which positive formal charges are on the most electronegative atoms.

Question 20

Which of the bonds below would have the greatest polarity (i.e., highest percent ionic character)

Accepted Answer

A)  Si - P 
B)  Si - S 
C)  Si - Se 
D)  Si - Cl 
E)  Si - I 
A)  Si - P 
B)  Si - S 
C)  Si - Se 
D)  Si - Cl 
E)  Si - I

Exam 9: Chemical Bonding I: Basic Concepts

The compound Al(ClO3)3 shows only ionic bonding.

What is the total number of lone pairs in the best Lewis structure for SOF4 that exceeds the octet rule (S is the central atom)

A Lewis structure of boron trifluoride is shown here. How many valence electrons are shown directly around the B atom

Which one of these polar covalent bonds would have the greatest percent ionic character

Assuming the octet rule is obeyed, how many covalent bonds will a carbon atom form to give a formal charge of zero

The Lewis structure shown here is correct for ammonia (nitrogen trihydride).

Which of the following ionic solids would have the largest lattice energy

The properties and chemical reactivity of a molecule is best explained by analyzing all possible resonance structures for that molecule.

Estimate the enthalpy change for the reaction 2CO + O2 →\rarr→ 2CO2 given the following bond energies. BE(C ≡\equiv≡ O) = 1074 kJ/mol BE(O=O) = 499 kJ/mol BE(C=O) = 802 kJ/mol

What is the formal charge on the singly bonded oxygens in the Lewis structure for the carbonate ion

The formal charge on the bromine atom in BrO3- drawn with three single bonds is

A nonpolar covalent bond (i.e., pure covalent) would form in which one of the following pairs of atoms

What is the formal charge on phosphorus in a Lewis structure for the phosphate ion that satisfies the octet rule

Which of the following solids would have the lowest melting point

Which one of the following molecules has an atom with an expanded octet

Define electronegativity:

Which one of the following is most likely to be an ionic compound

Use the Born-Haber cycle to calculate the lattice energy of KCl(s) given the following data: Δ\DeltaΔ H(sublimation) K = 79.2 kJ/mol I1 (K) = 418.7 kJ/mol Bond energy (Cl-Cl) = 242.8 kJ/mol EA (Cl) = 348 kJ/mol ΔHf∘\Delta{H}^{\circ}_fΔHf∘​ (KCl(s)) = -435.7 kJ/mol

Which of the following is a useful guideline for the application of formal charges in neutral molecules

Which of the bonds below would have the greatest polarity (i.e., highest percent ionic character)

Chemistry: The Study of Change

Atoms Molecules and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Gases

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding II: Molecular Geometry and Hybridization of Atomic

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy Free Energy and Equilibrium

Electrochemistry

Nuclear Chemistry

Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metals Chemistry and Coordination Compounds

Organic Chemistry

Synthetic and Natural Organic Polymers

Filters

The compound Al(ClO₃)₃ shows only ionic bonding.

What is the total number of lone pairs in the best Lewis structure for SOF₄ that exceeds the octet rule (S is the central atom)

Estimate the enthalpy change for the reaction 2CO + O₂ $\rarr$ 2CO₂ given the following bond energies. BE(C $\equiv$ O) = 1074 kJ/mol BE(O=O) = 499 kJ/mol BE(C=O) = 802 kJ/mol

The formal charge on the bromine atom in BrO₃^- drawn with three single bonds is

Use the Born-Haber cycle to calculate the lattice energy of KCl(s) given the following data: $\Delta$ H(sublimation) K = 79.2 kJ/mol I₁ (K) = 418.7 kJ/mol Bond energy (Cl-Cl) = 242.8 kJ/mol EA (Cl) = 348 kJ/mol $\Delta{H}^{\circ}_f$ (KCl(s)) = -435.7 kJ/mol