EXAM BANK: ORGANIC CHEMISTRY (7TH EDITION)
BY JANICE GORZYNSKI SMITH
ISBN: 9781264141531
TOTAL QUESTIONS: 150
SECTION 1: STRUCTURE AND BONDING (Questions 1-20)
QUESTION 1
What is the ground-state electron configuration of carbon?
A) 1s² 2s² 2p⁶
B) 1s² 2s² 2p²
C) 1s² 2s¹ 2p³
D) 1s² 2s² 2p⁴
ANSWER: B
EXPLANATION: Carbon has atomic number 6, so its ground-state configuration is 1s² 2s² 2p²
[citation:1].
QUESTION 2
How many covalent bonds does a neutral carbon atom typically form?
A) 2
B) 3
C) 4
D) 5
ANSWER: C
EXPLANATION: Carbon has four valence electrons and typically forms four covalent bonds to
achieve a complete octet [citation:1].
QUESTION 3
Which hybridization best describes the carbon atoms in methane (CH₄)?
A) sp
B) sp²
C) sp³
D) sp³d
ANSWER: C
EXPLANATION: Methane has four equivalent C–H bonds arranged tetrahedrally, which is
characteristic of sp³ hybridization [citation:1].
QUESTION 4
Which of the following molecules contains an sp²-hybridized carbon?
A) Ethane
,B) Ethylene (ethene)
C) Acetylene (ethyne)
D) Methane
ANSWER: B
EXPLANATION: Ethylene has a C=C double bond; each carbon of the double bond is sp²
hybridized [citation:1].
QUESTION 5
What is the approximate H–C–H bond angle in methane?
A) 90°
B) 109.5°
C) 120°
D) 180°
ANSWER: B
EXPLANATION: The tetrahedral geometry of sp³-hybridized carbon results in a bond angle of
approximately 109.5° [citation:1].
QUESTION 6
Which of the following is a non-polar molecule?
A) H₂O
B) NH₃
C) BF₃
D) CH₃Cl
ANSWER: C
EXPLANATION: BF₃ is trigonal planar; the three polar B–F bonds are symmetrically arranged
and cancel, resulting in no net dipole moment [citation:1].
QUESTION 7
The carbon–carbon triple bond of acetylene is composed of:
A) one σ bond and one π bond
B) one σ bond and two π bonds
C) two σ bonds and one π bond
D) three π bonds
ANSWER: B
EXPLANATION: A triple bond consists of one σ bond (end-on) and two orthogonal π bonds
(side-by-side) [citation:1].
QUESTION 8
What is the formal charge on oxygen in the hydronium ion (H₃O⁺)?
A) –1
, B) 0
C) +1
D) +2
ANSWER: C
EXPLANATION: In H₃O⁺, oxygen has three bonds and one lone pair. Formal charge = 6 – (2 +
3) = +1 [citation:1].
QUESTION 9
Which statement correctly describes resonance structures?
A) They are different compounds in equilibrium.
B) They are valid Lewis structures that differ only in the placement of π electrons and lone pairs.
C) They differ in the placement of σ bonds.
D) They are different molecular species with the same formula.
ANSWER: B
EXPLANATION: Resonance structures differ in the distribution of π electrons and non-bonding
electrons, not σ bonds or atom positions [citation:1].
QUESTION 10
What is the bond order of a C–O bond in the carbonate ion (CO₃²⁻)?
A) 1
B) 1.33
C) 1.5
D) 2
ANSWER: B
EXPLANATION: Three equivalent resonance structures give each C–O bond a bond order of
4/3 ≈ 1.33 [citation:1].
QUESTION 11
What is the hybridization of the nitrogen atom in ammonia (NH₃)?
A) sp
B) sp²
C) sp³
D) sp³d
ANSWER: C
EXPLANATION: The nitrogen in NH₃ is sp³ hybridized, with one lone pair occupying one of the
four sp³ orbitals [citation:1].
QUESTION 12
Which is the most electronegative element commonly found in organic compounds?
A) Carbon
BY JANICE GORZYNSKI SMITH
ISBN: 9781264141531
TOTAL QUESTIONS: 150
SECTION 1: STRUCTURE AND BONDING (Questions 1-20)
QUESTION 1
What is the ground-state electron configuration of carbon?
A) 1s² 2s² 2p⁶
B) 1s² 2s² 2p²
C) 1s² 2s¹ 2p³
D) 1s² 2s² 2p⁴
ANSWER: B
EXPLANATION: Carbon has atomic number 6, so its ground-state configuration is 1s² 2s² 2p²
[citation:1].
QUESTION 2
How many covalent bonds does a neutral carbon atom typically form?
A) 2
B) 3
C) 4
D) 5
ANSWER: C
EXPLANATION: Carbon has four valence electrons and typically forms four covalent bonds to
achieve a complete octet [citation:1].
QUESTION 3
Which hybridization best describes the carbon atoms in methane (CH₄)?
A) sp
B) sp²
C) sp³
D) sp³d
ANSWER: C
EXPLANATION: Methane has four equivalent C–H bonds arranged tetrahedrally, which is
characteristic of sp³ hybridization [citation:1].
QUESTION 4
Which of the following molecules contains an sp²-hybridized carbon?
A) Ethane
,B) Ethylene (ethene)
C) Acetylene (ethyne)
D) Methane
ANSWER: B
EXPLANATION: Ethylene has a C=C double bond; each carbon of the double bond is sp²
hybridized [citation:1].
QUESTION 5
What is the approximate H–C–H bond angle in methane?
A) 90°
B) 109.5°
C) 120°
D) 180°
ANSWER: B
EXPLANATION: The tetrahedral geometry of sp³-hybridized carbon results in a bond angle of
approximately 109.5° [citation:1].
QUESTION 6
Which of the following is a non-polar molecule?
A) H₂O
B) NH₃
C) BF₃
D) CH₃Cl
ANSWER: C
EXPLANATION: BF₃ is trigonal planar; the three polar B–F bonds are symmetrically arranged
and cancel, resulting in no net dipole moment [citation:1].
QUESTION 7
The carbon–carbon triple bond of acetylene is composed of:
A) one σ bond and one π bond
B) one σ bond and two π bonds
C) two σ bonds and one π bond
D) three π bonds
ANSWER: B
EXPLANATION: A triple bond consists of one σ bond (end-on) and two orthogonal π bonds
(side-by-side) [citation:1].
QUESTION 8
What is the formal charge on oxygen in the hydronium ion (H₃O⁺)?
A) –1
, B) 0
C) +1
D) +2
ANSWER: C
EXPLANATION: In H₃O⁺, oxygen has three bonds and one lone pair. Formal charge = 6 – (2 +
3) = +1 [citation:1].
QUESTION 9
Which statement correctly describes resonance structures?
A) They are different compounds in equilibrium.
B) They are valid Lewis structures that differ only in the placement of π electrons and lone pairs.
C) They differ in the placement of σ bonds.
D) They are different molecular species with the same formula.
ANSWER: B
EXPLANATION: Resonance structures differ in the distribution of π electrons and non-bonding
electrons, not σ bonds or atom positions [citation:1].
QUESTION 10
What is the bond order of a C–O bond in the carbonate ion (CO₃²⁻)?
A) 1
B) 1.33
C) 1.5
D) 2
ANSWER: B
EXPLANATION: Three equivalent resonance structures give each C–O bond a bond order of
4/3 ≈ 1.33 [citation:1].
QUESTION 11
What is the hybridization of the nitrogen atom in ammonia (NH₃)?
A) sp
B) sp²
C) sp³
D) sp³d
ANSWER: C
EXPLANATION: The nitrogen in NH₃ is sp³ hybridized, with one lone pair occupying one of the
four sp³ orbitals [citation:1].
QUESTION 12
Which is the most electronegative element commonly found in organic compounds?
A) Carbon
