Chemistry - A Molecular Science

Chapter 6 Molecular Structure & Bonding

128

6.7

EXERCISES

1.^

Draw the Lewis structure of each of the following ions, showing all nonzero formal charges. Indicate whether each ion is linear or bent. If the ion is bent, what is the bond angle?

a)

NO

1-^2

b)

N

1- 3

c)

ClO

1- 2

2.^

Draw the Lewis structure of each of the following molecules, showing all nonzero formal charges. Indicate whethe

r each molecule is linear or bent. If

the molecule is bent, what is the bond angle?

a)

N

O 2

b)

HCN

c)

OF

(^2)

3.^

Draw Lewis structures for the follo

wing molecules. Indicate nonzero

formal charges and whether each is trig

onal planar or trigonal pyramidal.

a)

PF

(^3)
b)
COCl
(^2)
c)
BF
(^3)

4.^

Draw Lewis structures for the follo

wing ions. Indicate nonzero formal

charge and whether each is planar or trigonal pyramidal.

a)

ClO

1- 3

b)

CO

2- 3

c)

PO

3- 3

5. Describe the shapes of the following:

a)^

ClF

(^3)
b)
XeF
(^4)
c)
ClF
(^5)

6.^

The Lewis structures of the sulfate and phosphate ions that obey the octet rule contain large, positive formal charges on the central atoms and an excess of negative formal charges on th

e oxygen atoms. Assume that S and

P use expanded valence shells and draw Lewis structures for the ions that contain no formal charge

on the central atoms.

7.^

What is the hybridization on th

e central atoms in Exercise 1?

8.^

What is the hybridization on the central atoms in Exercise 2?

9.^

What is the hybridization on th

e central atoms in Exercise 3?

10.

What is the hybridization on th

e central atoms in Exercise 4?

11.

We use the approximate bond angles of 120

o and 109

o around central atoms

with three and four electron groups, respectively. However, lone pairs affect bond angles differently than do bonding pairs. With this in mind, rank the following species in order

of increasing H-N-H bond angles:

NH

1-, NH 2

, and NH 3

1+ 4

.

12.

List the following in order of increasing bond angles: SO

, CO 2

and H 2

O. 2

13.

The nitrite ion (NO

1-) can add an H 2

1+ ion (proton) to become nitrous acid.

Based on the formal charges in the Le

wis structure of the anion (Exercise

1a), draw the Lewis structure of nitrous acid, HNO

. 2

14.

The carbonate ion (CO

2- 3

) can add two H

1+ ions to become carbonic acid.

Based on the formal charges in the Le

wis structure of the anion (Exercise

4b), draw the Lewis structure of carbonic acid, H

CO 2

. 3

15.

Explain why molecules A and C are pl

anar while molecule B is not.

CC

H H

H H

CCC

H H

HH

CCCC

H H

H H

(a) (b) (c)

16.

Acetaminophen is an analgesic (pain killer) that is often purchased under the name Tylenol

®. What are the approximate bond angles labeled

, α

, β

, γ

(^) δ
and
in the acetaminophen structure shown below?ε
CC
CC C
C
ON
C
C
O
HH
H
H
H
H H
H
H
α
β
γ
δ
ε
17.
Aspartame is the active ingredie
nt in the sweetener NutraSweet
®. What are
the approximate bond angles
, α
, β
, γ
and δ
in the aspartame structure ε
shown below?
α
β
γ
δ
ε
HN
H
C C C
HH
C
O
O C
H N
C
O
CHO
3
H
C H
H C
CC
CC C
HH
H
H
H
OH
C
HH
C
O
OH
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