Question 1

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)   4F) All of the above
G) A) and B)

Question 2

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.F) B) and E)
G) A) and D)

Question 3

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)   +2F) A) and C)
G) All of the above

Question 4

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 5

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.D) B) and C)
E) None of the above

Question 6

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 - IE) None of the above
F) C) and D)

Question 7

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 - BrF) A) and B)
G) A) and D)

Question 8

Which of the following solids would have the lowest melting point

Accepted Answer

A)   KI
B)   KBr
C)   KCl
D)   KFE) A) and B)
F) All of the above

Question 9

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 aboveF) B) and D)
G) B) and E)

Question 10

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

Accepted Answer

A)   SrO
B)   NaF
C)   CaBr2
D)   CsI
E)   BaSO4F) B) and E)
G) None of the above

Question 11

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

Accepted Answer

A) True 
 B)False

Question 12

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 bondsF) All of the above
G) B) and C)

Question 13

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

Accepted Answer

A) True 
 B)False

Question 14

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 - IF) A) and C)
G) All of the above

Question 15

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)   +2F) All of the above
G) C) and D)

Question 16

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)   18F) D) and E)
G) A) and C)

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)   OF2F) A) and C)
G) A) and D)

Question 18

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 F) C) and D)
G) A) and B)

Question 19

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

Accepted Answer

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

Question 20

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

Accepted Answer

A)   HCl
B)   AsCl5
C)   ICl
D)   NCl3
E)   Cl2F) A) and B)
G) A) and C)

Exam 9: Chemical Bonding I: Basic Concepts

Which of the following solids would have the lowest melting point

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Define electronegativity:

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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)

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

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)

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified