Question 1

Thionyl chloride is used as an oxidizing and chlorinating agent in organic chemistry. Select the best Lewis structure for SOCl2.

Accepted Answer

A)    
B)    
C)    
D)    
E)  None of the above structures is suitable for SOCl2. 
A)    
B)    
C)    
D)    
E)  None of the above structures is suitable for SOCl2.

Question 2

The formal charges on Cl and O in the structure shown for the ClO- ion are, respectively

Accepted Answer

A)  0 and -1 
B)  -1 and 0 
C)  1 and -2 
D)  -2 and 1 
E)  none of the above 
A)  0 and -1 
B)  -1 and 0 
C)  1 and -2 
D)  -2 and 1 
E)  none of the above

Question 3

Which one of the following Lewis structures is definitely incorrect?

Accepted Answer

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

Question 4

In which one of the following structures does the central atom have a formal charge of +2?

Accepted Answer

A)  SF6   
B)  SO42-   
C)  O3   
D)  BeCl2   
E)  AlCl4-   
A)  SF6   
B)  SO42-   
C)  O3   
D)  BeCl2   
E)  AlCl4-

Question 5

According to VSEPR theory, a molecule with the general formula AX3E2 will have a _____ molecular shape.

Accepted Answer

A)  trigonal pyramidal 
B)  trigonal bipyramidal 
C)  trigonal planar 
D)  T-shaped 
E)  see-saw 
A)  trigonal pyramidal 
B)  trigonal bipyramidal 
C)  trigonal planar 
D)  T-shaped 
E)  see-saw

Question 6

According to VSEPR theory, a molecule with the general formula AX2E2 will have a _____ molecular shape.

Accepted Answer

A)  linear 
B)  bent 
C)  trigonal planar 
D)  tetrahedral 
E)  see-saw 
A)  linear 
B)  bent 
C)  trigonal planar 
D)  tetrahedral 
E)  see-saw

Question 7

List the three important ways in which molecules can violate the octet rule, and in each case draw one Lewis structure of your choice as an example.

Accepted Answer

Electron-deficient molecules have fewer

Question 8

Predict the ideal bond angles around carbon in C2I2 using the molecular shape given by the VSEPR theory.

Accepted Answer

A)  90° 
B)  109° 
C)  120° 
D)  180° 
E)  none of the above 
A)  90° 
B)  109° 
C)  120° 
D)  180° 
E)  none of the above

Question 9

Use VSEPR theory to decide which one of the following molecules and ions will definitely have at least one 90° bond angle in it. (In each case except water, the central atom is the first one in the formula.)

Accepted Answer

A)  AlCl4- 
B)  NH3 
C)  PCl5 
D)  CO2 
E)  H2O 
A)  AlCl4- 
B)  NH3 
C)  PCl5 
D)  CO2 
E)  H2O

Question 10

What is the molecular shape of the thiocyanate anion, SCN-, as predicted by the VSEPR theory? (Carbon is the central atom.)

Accepted Answer

A)  linear 
B)  bent 
C)  angular 
D)  trigonal 
E)  none of the above 
A)  linear 
B)  bent 
C)  angular 
D)  trigonal 
E)  none of the above

Question 11

What is the molecular shape of NOCl as predicted by the VSEPR theory?

Accepted Answer

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

Question 12

Bond angles of 180° only occur around atoms which display linear molecular geometry.

Accepted Answer

A) True 
 B)False

Question 13

Draw Lewis structures, showing all valence electrons, for:
a. N
b. Br-
c. O2
d. SO42-

Accepted Answer

A)11ec6d40_88db_23e6_9cd1_6949936dcf2d_T

Question 14

What is the molecular shape of BeH2 as predicted by the VSEPR theory?

Accepted Answer

A)  linear 
B)  bent 
C)  angular 
D)  trigonal 
E)  none of the above 
A)  linear 
B)  bent 
C)  angular 
D)  trigonal 
E)  none of the above

Question 15

In which one of the following is the best Lewis structure a resonance structure? (central atoms are bold)

Accepted Answer

A)  CO2 
B)  ClO3- 
C)  COCl2 
D)  NO2+ 
E)  HCN 
A)  CO2 
B)  ClO3- 
C)  COCl2 
D)  NO2+ 
E)  HCN

Question 16

In which one of the following species is the central atom (the first atom in the formula) an exception to the octet rule?

Accepted Answer

A)  NH3 
B)  NH4+ 
C)  I2 
D)  BH4- 
E)  SF6 
A)  NH3 
B)  NH4+ 
C)  I2 
D)  BH4- 
E)  SF6

Question 17

In order for a non-cyclic triatomic molecule to be bent, VSEPR theory requires that there must be two lone pairs on the central atom.

Accepted Answer

A) True 
 B)False

Question 18

According to VSEPR theory, a molecule with the general formula AX5 will have a ______ molecular shape.

Accepted Answer

A)  tetrahedral 
B)  trigonal planar 
C)  trigonal pyramidal 
D)  trigonal bipyramidal 
E)  see-saw 
A)  tetrahedral 
B)  trigonal planar 
C)  trigonal pyramidal 
D)  trigonal bipyramidal 
E)  see-saw

Question 19

Select the best Lewis structure for ClCN.

Accepted Answer

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

Question 20

In formaldehyde, CH2O, both the formal charge and the oxidation number of carbon are zero.

Accepted Answer

A) True 
 B)False

Exam 10: The Shapes of Molecules

Thionyl chloride is used as an oxidizing and chlorinating agent in organic chemistry. Select the best Lewis structure for SOCl2.

The formal charges on Cl and O in the structure shown for the ClO- ion are, respectively

Which one of the following Lewis structures is definitely incorrect?

In which one of the following structures does the central atom have a formal charge of +2?

According to VSEPR theory, a molecule with the general formula AX3E2 will have a _____ molecular shape.

According to VSEPR theory, a molecule with the general formula AX2E2 will have a _____ molecular shape.

List the three important ways in which molecules can violate the octet rule, and in each case draw one Lewis structure of your choice as an example.

Predict the ideal bond angles around carbon in C2I2 using the molecular shape given by the VSEPR theory.

Use VSEPR theory to decide which one of the following molecules and ions will definitely have at least one 90° bond angle in it. (In each case except water, the central atom is the first one in the formula.)

What is the molecular shape of the thiocyanate anion, SCN-, as predicted by the VSEPR theory? (Carbon is the central atom.)

What is the molecular shape of NOCl as predicted by the VSEPR theory?

Bond angles of 180° only occur around atoms which display linear molecular geometry.

Draw Lewis structures, showing all valence electrons, for: a. N b. Br- c. O2 d. SO42-

What is the molecular shape of BeH2 as predicted by the VSEPR theory?

In which one of the following is the best Lewis structure a resonance structure? (central atoms are bold)

In which one of the following species is the central atom (the first atom in the formula) an exception to the octet rule?

In order for a non-cyclic triatomic molecule to be bent, VSEPR theory requires that there must be two lone pairs on the central atom.

According to VSEPR theory, a molecule with the general formula AX5 will have a ______ molecular shape.

Select the best Lewis structure for ClCN.

In formaldehyde, CH2O, both the formal charge and the oxidation number of carbon are zero.

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

The 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

Models of Chemical Bonding

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: Bonding, Structure, and Reactivity

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

Thionyl chloride is used as an oxidizing and chlorinating agent in organic chemistry. Select the best Lewis structure for SOCl₂.

The formal charges on Cl and O in the structure shown for the ClO^-ion are, respectively

According to VSEPR theory, a molecule with the general formula AX₃E₂will have a _____ molecular shape.

According to VSEPR theory, a molecule with the general formula AX₂E₂will have a _____ molecular shape.

Predict the ideal bond angles around carbon in C₂I₂using the molecular shape given by the VSEPR theory.

What is the molecular shape of the thiocyanate anion, SCN^-, as predicted by the VSEPR theory? (Carbon is the central atom.)

Draw Lewis structures, showing all valence electrons, for: a. N b. Br^- c. O₂ d. SO₄^2-

What is the molecular shape of BeH₂as predicted by the VSEPR theory?

According to VSEPR theory, a molecule with the general formula AX₅ will have a ______ molecular shape.

In formaldehyde, CH₂O, both the formal charge and the oxidation number of carbon are zero.