Deck 10: The Shapes of Molecules

Question 1

Select the correct Lewis structure for NOCl, a reactive material used as an ionizing solvent.

A)
B)
C)
D)
E) None of these choices are correct.

Answer 1

Question 2

How many electron pairs are shared between the carbon atoms in C₂H₄?

A) 5
B) 4
C) 3
D) 2
E) 1

Answer 2

2

Question 3

Select the best Lewis structure for ClCN.

A)
B)
C)
D)
E)

Answer 3

Question 4

In neutral molecules, how many bonds are commonly formed by nitrogen? And how many by oxygen?

A) 5 and 6
B) 4 and 2
C) 3 and 6
D) 4 and 6
E) 3 and 2

Question 5

Hydrazine, N₂H₄, is a good reducing agent that has been used as a component in rocket fuels. Select its Lewis structure.

A)
B)
C)
D)
E) None of these choices are correct.

Question 6

Which one of the following Lewis structures is definitely incorrect?

A)
B)
C)
D)
E)

Question 7

Oxygen difluoride is a powerful oxidizing and fluorinating agent. Select its Lewis structure.

A)
B)
C)
D)
E) None of these choices are correct.

Question 8

Which one of the following molecules contains a double bond?

A) N₂
B) PCl₅
C) CH₂O
D) C₂H₂
E) I₂

Question 9

Select the best Lewis structure for P₂I₄.

A)
B)
C)
D)
E) None of these choices are correct.

Question 10

Select the correct Lewis structure for TeBr₂.

A)
B)
C)
D)
E)

Question 11

Select the correct Lewis structure for nitrogen trifluoride, NF₃.

A)
B)
C)
D)
E)

Question 12

In which one of the following is the best Lewis structure a resonance structure?

A) SO₃
B) BF₃
C) I₃^-
D) SCO (C = central atom)
E) SO₃^2-

Question 13

Which one of the following Lewis structures is definitely incorrect?

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

Question 14

In carbon disulfide, how many lone pairs of electrons are on each sulfur atom?

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

Question 15

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

A)
B)
C)
D)
E) None of these choices are correct.

Question 16

In the nitrate ion (NO₃^-), nitrogen and oxygen are held together by

A) ionic interactions.
B) covalent bonds.
C) dative bonds.
D) electronegativity.
E) network bonds.

Question 17

In which one of the following molecules are all the bonds single?

A) O₃
B) POCl₃
C) CO
D) COCl₂
E) N₂H₄

Question 18

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

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

Question 19

How many resonance structures are possible for NO₃^-?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 20

Which one of the following Lewis structures is definitely incorrect?

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

Question 21

In which of the following does the nitrogen atom have a formal charge of -1?

A)
B)
C)
D)
E)

Question 22

Considering all the bonds in a molecule with trigonal bipyramidal geometry, what are the bond angles present?

A) 120° only
B) 90° only
C) 180° only
D) 60° and 90° only
E) 90°, 120°, and 180°

Question 23

Which of the following atoms can expand its valence shell when bonding?

A) N
B) C
C) O
D) P
E) Al

Question 24

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

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

Question 25

In the COCl₂ molecule, carbon is the central atom. Based on the best Lewis structure for COCl₂, what is the formal charge on carbon?

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

Question 26

In the following Lewis structure for ClO₃F, chlorine has a formal charge of ____ and an oxidation number of ____.

A) 7; 7
B) 7; -1
C) 1; 1
D) 1; -1
E) 1; 7

Question 27

According to VSEPR theory, a molecule with the general formula AX₃ will have a ______ molecular shape.

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

Question 28

Phosphoryl iodide is used in the preparation of organophosphorus derivatives and phosphate esters. Select the Lewis structure for POI₃ that minimizes formal charges.

A)
B)
C)
D)
E)

Question 29

In which one of the following species is the best Lewis structure a resonance structure?

A) NH₃
B) CO₂
C) SF₆
D) O₂
E) CO₃^2-

Question 30

Select the Lewis structure in which formal charges are minimized for the periodate anion, IO₄^-.

A)
B)
C)
D)
E)

Question 31

The formal charge on Cl in the structure shown for the perchlorate ion is

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

Question 32

According to VSEPR theory, a molecule with the general formula AX₂ will have a ___ molecular shape.

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

Question 33

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

A) BF₄^-
B) XeO₃
C) SiCl₄
D) NH₃
E) CH₂Cl₂

Question 34

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

A)
B)
C)
D)
E)

Question 35

The best Lewis structure for sulfuric acid has zero formal charges, sulfur as the central atom, and no bonds between S and H. How many single and double bonds, respectively, are there in this Lewis structure?

A) 2 single, 4 double
B) 4 single, 2 double
C) 4 single, no double
D) 6 single, no double
E) 5 single, 1 double

Question 36

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

A) 0 and -1
B) -1 and 0
C) 1 and -2
D) -2 and 1
E) None of these choices are correct.

Question 37

According to VSEPR theory, a molecule with the general formula AX₄ will have a ______ molecular shape.

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

Question 38

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

A) NH₃
B) NH₄⁺
C) I₂
D) BH₄^-
E) SF₆

Question 39

In the following Lewis structure for phosphate, phosphorus has a formal charge of ____ and an oxidation number of ____.

A) 0; -3
B) 0; 5
C) 5; -3
D) 5; 5
E) 3; 5

Question 40

Select the Lewis structure for XeO₂F₂ that correctly minimizes formal charges.

A)
B)
C)
D)
E)

Question 41

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

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

Question 42

According to VSEPR theory, a molecule with the general formula AX₂E₃ will have a _____ molecular shape.

A) bent
B) linear
C) trigonal planar
D) T-shaped
E) trigonal pyramidal

Question 43

According to VSEPR theory, a molecule with the general formula AX₆ will have a ______ molecular shape.

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

Question 44

What is the molecular symmetry around the carbons in CCl₂CH₂ as predicted by the VSEPR theory?

A) linear
B) trigonal planar
C) V-shaped
D) tetrahedral
E) trigonal pyramidal

Question 45

What is the molecular shape of ClO₃F as predicted by the VSEPR theory?

A) trigonal pyramidal
B) square planar
C) square pyramidal
D) tetrahedral
E) octahedral

Question 46

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

A) linear
B) bent
C) angular
D) trigonal
E) None of these choices are correct.

Question 47

According to VSEPR theory, a molecule with the general formula AX₄E will have a _____ molecular shape.

A) bent
B) see-saw
C) trigonal planar
D) T-shaped
E) square planar

Question 48

According to VSEPR theory, a molecule with the general formula AX₂E will have a ______ molecular shape.

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

Question 49

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

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

Question 50

What is the molecular shape of BCl₃ as predicted by the VSEPR theory?

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

Question 51

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

A) linear
B) bent
C) angular
D) trigonal
E) None of these choices are correct.

Question 52

According to VSEPR theory, a molecule with the general formula AX₃E will have a _____ molecular shape.

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

Question 53

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

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

Question 54

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

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

Question 55

According to VSEPR theory, a molecule with the general formula AX₅E will have a ______ molecular shape.

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

Question 56

How many faces and how many vertexes (corners), respectively, are there in a trigonal bipyramid?

A) 4 and 4
B) 5 and 5
C) 5 and 6
D) 6 and 5
E) 6 and 8

Question 57

According to VSEPR theory, a molecule with the general formula AX₄E₂ will have a _____ molecular shape.

A) tetrahedral
B) square pyramidal
C) square planar
D) octahedral
E) see-saw

Question 58

What is the molecular shape of NO₂^- as predicted by the VSEPR theory?

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

Question 59

What is the molecular shape of N₂O as predicted by the VSEPR theory?

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

Question 60

What is the molecular shape of ClCN as predicted by the VSEPR theory? (Carbon is the central atom.)

A) linear
B) bent
C) angular
D) trigonal
E) None of these choices are correct.

Question 61

Predict the ideal bond angles in IF₂^- using the molecular shape given by the VSEPR theory.

A) 60°
B) 90°
C) 109°
D) 120°
E) 180°

Question 62

What is the molecular shape of XeO₂F₂ as predicted by the VSEPR theory?

A) square planar
B) tetrahedral
C) square pyramidal
D) see-saw
E) octahedral

Question 63

Predict the actual bond angles in SF₃⁺ using the VSEPR theory.

A) more than 120°
B) exactly 120°
C) between 109° and 120°
D) between 90° and 109°
E) less than 90°

Question 64

Use VSEPR theory to predict the electron group arrangement around iodine, the central atom in the ion IF₂^-.

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

Question 65

Predict the ideal bond angles around nitrogen in N₂F₂ using the molecular shape given by the VSEPR theory. (The two N atoms are the central atoms.)

A) 90°
B) 109°
C) 120°
D) 180°
E) between 120 and 180°

Question 66

What is the molecular shape of SCl₃F as predicted by the VSEPR theory?

A) linear
B) bent
C) see-saw
D) T-shaped
E) trigonal pyramidal

Question 67

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

A) 90°
B) 109°
C) 120°
D) 180°
E) None of these choices are correct.

Question 68

Use VSEPR theory to decide which one of the following molecules and ions will have a trigonal pyramidal geometry. (The central atom is always first in the formula.)

A) PCl₃
B) BF₃
C) SO₃
D) BrF₃
E) CO₃^2-

Question 69

What is the molecular shape of SiF₆^2- as predicted by the VSEPR theory?

A) trigonal bipyramidal
B) hexagonal
C) tetrahedral
D) see-saw
E) octahedral

Question 70

What is the molecular shape of NH₂Cl as predicted by the VSEPR theory?

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

Question 71

Predict the ideal bond angles in FNO using the molecular shape given by the VSEPR theory.

A) 90°
B) 109°
C) 120°
D) 180°
E) between 120 and 180°

Question 72

Predict the actual bond angle in SeCl₂ using the VSEPR theory.

A) more than 120°
B) between 109° and 120°
C) between 90° and 109°
D) exactly 90°
E) less than 90°

Question 73

What is the molecular shape of ClF₂^- as predicted by the VSEPR theory?

A) linear
B) bent
C) see-saw
D) T-shaped
E) L-shaped

Question 74

Use VSEPR theory to decide which one of the following ions and molecules is likely to be planar. (The central atom is always first in the formula.)

A) BrF₃
B) H₃O⁺
C) PCl₃
D) SO₄^2-
E) SF₄

Question 75

Which one of the following molecules and ions will have a planar geometry?

A) PCl₃
B) BF₄^-
C) XeF₄
D) BrF₅
E) H₃O⁺

Question 76

Predict the ideal bond angles in GeCl₄ using the molecular shape given by the VSEPR theory.

A) 90°
B) 109°
C) 120°
D) 180°
E) < 90°

Question 77

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.)

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

Question 78

Predict the ideal bond angles in AsCl₃ using the molecular shape given by the VSEPR theory.

A) 90°
B) 109°
C) 120°
D) 180°
E) between 110 and 120°

Question 79

Predict the smallest actual bond angle in BrF₃ using the VSEPR theory.

A) more than 120°
B) exactly 120°
C) between 109° and 120°
D) between 90° and 109°
E) less than 90°

Question 80

What is the molecular shape of ClF_4- as predicted by the VSEPR theory?

A) square pyramidal
B) square planar
C) see-saw
D) octahedral
E) tetrahedral