Question 1

Which of the following molecules or ions has a linear molecular geometry?

Accepted Answer

A)  H2O 
B)  H2S 
C)  ICl3 
D)  I3- 
E)  SO2 
A)  H2O 
B)  H2S 
C)  ICl3 
D)  I3- 
E)  SO2

Question 2

Which statement A-D about VSEPR theory is not correct?

Accepted Answer

A)  The molecular shape or geometry can differ from the electron-pair geometry. 
B)  In VSEPR theory, the shape or geometry of a molecule is determined by electron-electron repulsion. 
C)  The steric number of a central atom is the sum of the number of bonds and lone pairs around the atom. 
D)  The steric number has five values from 2 to 6. 
E)  Statements A-D are all correct. 
A)  The molecular shape or geometry can differ from the electron-pair geometry. 
B)  In VSEPR theory, the shape or geometry of a molecule is determined by electron-electron repulsion. 
C)  The steric number of a central atom is the sum of the number of bonds and lone pairs around the atom. 
D)  The steric number has five values from 2 to 6. 
E)  Statements A-D are all correct.

Question 3

Which of the following has a central atom with the same hybridization as the carbon in formaldehyde (CH2O)?

Accepted Answer

A)  SO2 
B)  OCS 
C)  ICl3 
D)  I3- 
E)  C2H2 
A)  SO2 
B)  OCS 
C)  ICl3 
D)  I3- 
E)  C2H2

Question 4

Which of the following molecules has a carbon atom that is sp3 hybridized?

Accepted Answer

A)  C2H2 
B)  H2CO 
C)  CH3Cl 
D)  C2H4 
E)  C2H2Cl2 
A)  C2H2 
B)  H2CO 
C)  CH3Cl 
D)  C2H4 
E)  C2H2Cl2

Question 5

Broccoli, cabbage, and kale contain compounds that break down in the human body to form isothiocyanates that may reduce the risk of certain types of cancer. Methyl isothiocyanate (CH3NCS) is the simplest member of this family of compounds. Use formal charge to identify the most stable Lewis structure for this compound. Based on this structure, predict the local molecular geometry and hybridization at each atom except hydrogen.

Accepted Answer

The structure with all formal charges eq

Question 6

For the series methane, ammonia, and water, the bond angle increases in the following order: H2O 3 4. This trend is due to ________

Accepted Answer

A)  a decreasing effective nuclear charge. 
B)  a decrease in the number of lone pairs. 
C)  an increase in atomic radius. 
D)  an increase in the polarity of the molecules. 
E)  an increasing effective nuclear charge. 
A)  a decreasing effective nuclear charge. 
B)  a decrease in the number of lone pairs. 
C)  an increase in atomic radius. 
D)  an increase in the polarity of the molecules. 
E)  an increasing effective nuclear charge.

Question 7

A Lewis structure of aspirin without the nonbonding electrons is shown in the figure below. Identify the hybridization of the C1 and C2 atomic orbitals. Arrange the bonds (B2-B5) in order of increasing length.

Accepted Answer

C1 and C2 are sp² hybridized. B

Question 8

Which bond is the most polar?

Accepted Answer

A)  carbon-oxygen 
B)  carbon-sulfur 
C)  carbon-nitrogen 
D)  carbon-hydrogen 
E)  carbon-chlorine 
A)  carbon-oxygen 
B)  carbon-sulfur 
C)  carbon-nitrogen 
D)  carbon-hydrogen 
E)  carbon-chlorine

Question 9

What is the valence electron molecular orbital electron configuration of F2?

Accepted Answer

A)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \sigma _ { 2 p } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 2 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 }$$ 
B)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 6 } \left( \sigma _ { 2 s } \right) ^ { 2 } \left( \pi _ { 2p } ^ { * } \right) ^ { 2 }$$ 
C)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \sigma _ { 2p } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 4 }$$ 
D)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 4 }$$ 
E)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2p } \right) ^ { 4 } \left( \sigma _ { 2 p } \right) ^ { 2 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 2 }$$ 
A)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \sigma _ { 2 p } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 2 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 }$$ 
B)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 6 } \left( \sigma _ { 2 s } \right) ^ { 2 } \left( \pi _ { 2p } ^ { * } \right) ^ { 2 }$$ 
C)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \sigma _ { 2p } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 4 }$$ 
D)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } \right) ^ { 4 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 4 }$$ 
E)  $$\left( \sigma _ { 2 s } \right) ^ { 2 } \left( \sigma _ { 2 s } ^ { * } \right) ^ { 2 } \left( \pi _ { 2p } \right) ^ { 4 } \left( \sigma _ { 2 p } \right) ^ { 2 } \left( \sigma _ { 2 p } ^ { * } \right) ^ { 2 } \left( \pi _ { 2 p } ^ { * } \right) ^ { 2 }$$

Question 10

The correct H-N-H bond angle in NH3 is ________

Accepted Answer

A)  the same as the H-O-H angle in water. 
B)  exactly 109.5$\degree$. 
C)  greater than 109.5$\degree$. 
D)  less than 109.5°. 
E)  120°. 
A)  the same as the H-O-H angle in water. 
B)  exactly 109.5$\degree$. 
C)  greater than 109.5$\degree$. 
D)  less than 109.5°. 
E)  120°.

Question 11

Which statement A-D about valence bond theory is not correct?

Accepted Answer

A)  Valence bond theory describes a bond as the overlap of atomic orbitals between two atoms. 
B)  Enhanced electron density between two positively charged nuclei attracts the nuclei together and forms the bond. 
C)  Hybridization of atomic orbitals is necessary to account for the molecular geometry. 
D)  In valence bond theory, hybridization determines the molecular shape or geometry. 
E)  Statements A-D are all correct. 
A)  Valence bond theory describes a bond as the overlap of atomic orbitals between two atoms. 
B)  Enhanced electron density between two positively charged nuclei attracts the nuclei together and forms the bond. 
C)  Hybridization of atomic orbitals is necessary to account for the molecular geometry. 
D)  In valence bond theory, hybridization determines the molecular shape or geometry. 
E)  Statements A-D are all correct.

Question 12

What is the molecular geometry of the triiodide ion (I3-)?

Accepted Answer

A)  linear 
B)  bent 
C)  tetrahedral 
D)  trigonal pyramidal 
E)  trigonal planar 
A)  linear 
B)  bent 
C)  tetrahedral 
D)  trigonal pyramidal 
E)  trigonal planar

Question 13

Which electron-pair geometry corresponds to a steric number of 6?

Accepted Answer

A)  linear 
B)  trigonal planar 
C)  tetrahedral 
D)  trigonal bipyramidal 
E)  octahedral 
A)  linear 
B)  trigonal planar 
C)  tetrahedral 
D)  trigonal bipyramidal 
E)  octahedral

Question 14

Which of the following compounds has the same molecular shape as CCl3H?

Accepted Answer

A)  SiF4 
B)  KrF4 
C)  SF4 
D)  C2H4 
E)  C2H2 
A)  SiF4 
B)  KrF4 
C)  SF4 
D)  C2H4 
E)  C2H2

Question 15

A triatomic molecule with a bond angle close to 120o could be ________.

Accepted Answer

A)  SO2 
B)  N2O 
C)  HCN 
D)  CO2 
E)  BeH2 
A)  SO2 
B)  N2O 
C)  HCN 
D)  CO2 
E)  BeH2

Question 16

What type of hybridization is needed to describe the bonding in a T-shaped molecule?

Accepted Answer

A)  sp2 
B)  sp3 
C)  sp3d 
D)  sp 
E)  sp3d2 
A)  sp2 
B)  sp3 
C)  sp3d 
D)  sp 
E)  sp3d2

Question 17

Which type of molecular orbital is used to describe electron density building up above and below the internuclear axis to form a bond?

Accepted Answer

A) ($\sigma$) 
B) ( $\pi$) 
C)  ($\sigma$*) 
D)  ( $\pi$*) 
E)  s 
A) ($\sigma$) 
B) ( $\pi$) 
C)  ($\sigma$*) 
D)  ( $\pi$*) 
E)  s

Question 18

Which of the following has the largest bond angle?

Accepted Answer

A)  CF4 
B)  NF3 
C)  F2O 
D)  NF2- 
E)  NH3 
A)  CF4 
B)  NF3 
C)  F2O 
D)  NF2- 
E)  NH3

Question 19

In VSEPR theory, molecular geometry is determined by ________

Accepted Answer

A)  electron-proton attractive forces. 
B)  electron-electron attractive forces. 
C)  electron-electron repulsive forces. 
D)  proton-proton repulsive forces. 
E)  electron-nucleus attractive forces. 
A)  electron-proton attractive forces. 
B)  electron-electron attractive forces. 
C)  electron-electron repulsive forces. 
D)  proton-proton repulsive forces. 
E)  electron-nucleus attractive forces.

Question 20

This diagram shows the structure of two different spices: spearmint and caraway. Why do these molecules have different properties?

Accepted Answer

A)  They have different molecular formulas. 
B)  They are different structural isomers. 
C)  They are stereoisomers but not optical isomers. 
D)  They are optical isomers. 
E)  They are achiral. 
A)  They have different molecular formulas. 
B)  They are different structural isomers. 
C)  They are stereoisomers but not optical isomers. 
D)  They are optical isomers. 
E)  They are achiral.

Exam 9: Molecular Geometry: Shape Determines Function

Which of the following molecules or ions has a linear molecular geometry?

Which statement A-D about VSEPR theory is not correct?

Which of the following has a central atom with the same hybridization as the carbon in formaldehyde (CH2O)?

Which of the following molecules has a carbon atom that is sp3 hybridized?

For the series methane, ammonia, and water, the bond angle increases in the following order: H2O < NH3 < CH4. This trend is due to ________

A Lewis structure of aspirin without the nonbonding electrons is shown in the figure below. Identify the hybridization of the C1 and C2 atomic orbitals. Arrange the bonds (B2-B5) in order of increasing length.

Which bond is the most polar?

What is the valence electron molecular orbital electron configuration of F2?

The correct H-N-H bond angle in NH3 is ________

Which statement A-D about valence bond theory is not correct?

What is the molecular geometry of the triiodide ion (I3-)?

Which electron-pair geometry corresponds to a steric number of 6?

Which of the following compounds has the same molecular shape as CCl3H?

A triatomic molecule with a bond angle close to 120o could be ________.

What type of hybridization is needed to describe the bonding in a T-shaped molecule?

Which type of molecular orbital is used to describe electron density building up above and below the internuclear axis to form a bond?

Which of the following has the largest bond angle?

In VSEPR theory, molecular geometry is determined by ________

This diagram shows the structure of two different spices: spearmint and caraway. Why do these molecules have different properties?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: the Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Intermolecular Forces: The Uniqueness of Water

Solutions: Properties and Behavior

Solids: Structures and Applications

Organic Chemistry: Fuels, Pharmaceuticals, Materials, and Life

Chemical Kinetics: Reactions in the Air We Breathe

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acid-Base and Solubility Equilibria: Reactions in Soil and Water

Metal Ions: Colorful and Essential

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Electrochemistry: the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry: Applications to Energy and Medicine

Life and the Periodic Table

Filters

Which of the following has a central atom with the same hybridization as the carbon in formaldehyde (CH₂O)?

Which of the following molecules has a carbon atom that is sp³ hybridized?

For the series methane, ammonia, and water, the bond angle increases in the following order: H₂O < NH₃ < CH₄. This trend is due to ________

What is the valence electron molecular orbital electron configuration of F₂?

The correct H-N-H bond angle in NH₃ is ________

What is the molecular geometry of the triiodide ion (I₃^-)?

Which of the following compounds has the same molecular shape as CCl₃H?

A triatomic molecule with a bond angle close to 120^o could be ________.