Chemistry Reference
In-Depth Information
Ignoring
x
when subtracted from 0.0500 yields
19.17
The solution has a pH of 7.00. Because the salt is composed of
two ions, neither of which reacts with water, the solution is
neutral. The pH of a neutral solution is 7.00.
19.19 (a)
x
2
(0.0250) (0.0500)
2
5.00
10
6
K
4.67
10
8
3.6
10
7
(b)
x
2
10
10
3.1
3
4.65
10
14
6.0
10
5
(c)
(d)
10
5
x
1.7
7
[NO
2
]
8.7
10
7
(e)
0.101
(f )
10
5
[O
2
]
0.0500
x
0.0500
1.7
7
0.0500
19.20
H
2
S
is a weak acid.
[N
2
]
(0.0500
x
)
2
0.0250
19.22
H
2
S
(only
K
1
has an effect on pH.)
10
5
)
2
(0.0250) (0.0500)
2
(1.7
7
10
6
Check:
5.0
19.23
H
2
C
2
O
4
and
H
2
S
1.1
10
12
9.5
4
10
5
10
6
)%
18.62
Because an equilibrium system is
dynamic
(that is, reaction
continues in both directions), we expect both the combination
reaction and the decomposition reaction to proceed. There-
fore, some should react with some and some HD
will be formed. The reaction of the and the HD with
will result in the formation of some and
molecules. The existence of molecules with both and D in
them proves that both reactions are still occurring, even
though at equilibrium no
net reaction
occurs.
19.24 (a)
100%
(1.2
(b)
100%
HSO
3
19.26 (a) (b) (c)
19.28 (a) (b) (c) (d)
19.30 (a)
Basic (The solution contains a feeble acid and a weak
base,
(b)
Basic (The solution contains a feeble acid and a weak
base,
(c)
Basic (The solution contains a feeble acid and a weak
base,
(d)
Neutral
(e)
Acidic (The solution contains a weak acid,
NO
2
HSO
4
ND
3
NH
3
,
H
2
O
H
2
O
HNO
2
NH
3
D
2
N
2
ND
3
,
NHD
2
,
NH
2
D
1
H
C
2
H
3
O
2
.)
S
2
.)
NO
2
.)
19 Acid-Base Theory
19.1
NH
4
,
and a
Compounds
(a), (b), (d),
and
(e)
exist essentially as ions.
(a)
feeble base.)
K
ClO
2
H
BrO
3
(b)
ClO
4
(c)
CH
3
OH
(d)
NH
4
19.32 (a)
H
Mg
2
2 HCO
3
(e)
(f )
H
3
PO
3
HH
N
H
HCH
H
N
H
19.2
(a)
is weak; no ions are 0.100 M.
(b)
and
(c)
HClO is weak
(d)
HNO
2
Na
NO
3
(b)
The nitrogen atom's lone electron pair can be “donated”
to H
.
Na
ClO
and
(c)
H
H
H
19.4
(a)
Strong
(b)
Weak
(c)
Weak
(d)
Strong
HN
H
H
HN
HH
C
H
(e)
Weak
(f )
Strong
(g)
Weak
(h)
Strong
19.5
(a)
Strong
(b)
Strong
(c)
Weak
(d)
Weak
Acid
Base
19.33
(e)
Strong
19.6
The salt consists of the conjugate acid of a base (the cation)
and the conjugate base of an acid (the anion).
19.7
The cations are (and
These are the cations of the strong bases containing one
ion per formula unit.
19.8
Because is a salt, it is present in solution in the
form of and ions. The concentration 0.433 M
means that the solution was made up with 0.433 mol of
per liter of solution; it does not mean that un-
ionized molecules of are present in the solution.
The is 0.433 M; the is
19.10
Any strong acid could be used to provide the ions,
and any soluble metal nitrite could be used to provide the
anion. For example HCl,
H
3
O
OH
(a)
(b)
SO
4
2
H
2
SO
4
Li
,
Na
,
K
,
Rb
,
Cs
,
Fr
Ag
).
19.35
HNO
2
(aq)
H
2
O(
)
2
(aq)
H
3
O
(aq)
E
OH
Acid
Base
Base
Acid
Al(NO
3
)
3
Al
3
NO
3
C
5
H
5
NH
(aq)
OH
(aq)
C
5
H
5
N(aq)
H
2
O(
)
E
Al(NO
3
)
3
Base
Acid
Acid
Base
Al(NO
3
)
3
Al
3
NO
3
3(0.433 M)
1.30 M.
H
3
O
HSO
4
(aq)
H
3
O
(aq) E H
2
SO
4
(aq)
19.38
H
2
O(
)
Ba(NO
2
)
2
,
and
NaNO
2
could be
Base
Acid
Acid
Base
used.
H
2
O(
/
) E CN
(aq)
H
3
O
(aq)
19.11
HCN(aq)
Acid
Base
Base
Acid
NH
4
(aq)
OH
(aq) E NH
3
(aq)
H
2
O(
/
)
19.12
HSO
4
(aq)
OH
(aq) E SO
4
2
(aq)
H
2
O(
)
Acid
Acid
Base
Base
Acid
Base
Base
Acid
pH
log
[H
3
O
]
19.13 (a)
(b)
log
(0.400)
0.398
pH
0.398
(The HCl ionizes completely, yielding
.
H
3
O
.
19.39 (a)
The solution is 0.180 M
NH
3
and 0.060 M
NH
4
0.400 M
)
.
(b)
The solution is 0.180 M
NH
3
and 0.060 M
NH
4
19.15 (a)
3.341
(b)
6.752
(c)
3.218
NH
4
The
ions resulted from the partial neutralization of
(d)
8.478
(e)
0.000
(f )
0.301
the
(c)
No. (The concentration of
NH
3
.
19.16 (a)
Basic
(b)
Acidic
(c)
Basic
NH
3
is not lowered signifi-
(d)
Neutral
(e)
Neutral
(f )
Basic
cantly by its ionization.)
