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Chapter 2
Copyright © 2017 Pearson Education, Inc.
Solutions to Problems
1.
CO
2
and
CCl
4
are not acids because neither has a proton that it can lose.
2.
a.
HBr
b.
-
C
‚
N
c.
Br
-
d.
HC
‚
N
e.
HC
‚
N
f.
Br
-
g.
-
C
‚
N
h.
HBr
3.
a.
−
+
Cl
HCl
+
+
NH
3
NH
4
b.
−
−
H
2
O
HO
+
+
NH
2
NH
3
4.
The conjugate acid is obtained by adding an
H
+
to the species.
a. (1)
+
NH
4
(2)
HCl
(3)
H
2
O
(4)
H
3
O
+
The conjugate base is obtained by removing an
H
+
from the species.
b. (1)
-
NH
2
(2)
Br
-
(3)
NO
3
-
(4)
HO
-
5.
a.
The lower the
p
K
a
,
the stronger the acid, so the compound with
p
K
a
=
5.2
is the stronger acid.
b.
The greater the dissociation constant, the stronger the acid, so the compound with a dissociation
constant
=
3.4
*
10
-
3
is the stronger acid.
6.
Because we know that
K
a
=
K
eq
3
H
2
O
4
K
eq
=
K
a
3
H
2
O
4
=
4.53
*
10
-
6
55.5
=
8.16
*
10
-
8
7.
Its
K
a
value is
1.51
*
10
-
5
.
It is a weaker acid than vitamin C whose
K
a
value was determined to be
6.8
*
10
-
5
in the Problem-Solving Strategy.
8.
a.
+
HO
−
H
+
H
2
O
b.
HCO
3
−
+
H
+
H
2
CO
3
H
2
O
+
CO
2
c.
CO
3
2
−
+
2 H
+
H
2
CO
3
H
2
O
+
CO
2
9.
If the pH is
6
7,
the body fluid is acidic; if the pH is
7
7,
the body fluid is basic.
a.
basic
b.
acidic
c.
basic
10.
Remember that a proton can be picked up by an atom that has one or more lone pairs. Notice that two oxygens
have lone pairs in part
e
. To see which one gets the proton, see Table 2.1 on page 57 of the text and the
Problem-Solving Strategy on page 68.
a.
b.
c.
d.
e.
CH
3
CH
2
OH
2
CH
3
CH
2
OH
CH
OH
3
CH
2
NH
3
C
OH
OH
CH
3
CH
2
+
+
+
C
O
CH
3
11.
In each of the following reactions, the position of equilibrium is established by analyzing the relative strengths
of the acids on either side of the reaction—the equilibrium favors reaction of the stronger acid to form the
weaker acid (see Section 2.5). (Note that HCl is a stronger acid than
H
3
O
+
; see Appendix I in the text.)