SOLUTIONS TO SELECTED PROBLEMS IN CHAP. 9 & 10
The Arrhenius Theory (Section 9.1)
9.1
Write the dissociation equations for the following that emphasize their behavior
as Arrhenius acids: a) HI
b) HBrO
c) HCN
d) HClO
2
Solution
a) HI(aq) H
+
-
b) HBrO(aq) H
+
-
(aq) + I
(aq)
(aq) + BrO
(aq)
c) HCN(aq) H
(aq) H
+
-
+
-
(aq) + ClO
(aq) + CN
(aq)
d) HClO
(aq)
2
2
9.3
Each of the following produces a basic solution when dissolved in water. Identify
those that behave as Arrhenius bases and write dissociation equations to
illustrate that behavior. a) CsOH
b) CH
NH
c) NH
d) Ca(OH)
3
2
3
2
Solution
a) CsOH(aq) Cs
+
-
(aq) + OH
(aq)
b) not an Arrhenius base
(aq) Ca
2+
-
c) not an Arrhenius base
d) Ca(OH)
(aq) + 2OH
(aq)
2
The Br
nsted Theory (Section 9.2)
Ø
9.5
Identify each Br
nsted acid and base in the following equations. Note that the
Ø
reactions are assumed to be reversible.
+
-
2 -
-
-
HBr (aq) + H
O (l)
H
O
(aq) + Br
(aq)
d) SO
(aq)+H
O(l)
HSO
(aq)+OH
(aq)
a)
2
3
2
3
3
-
-
H
O (l) + N
(aq)
NH
(aq) + OH
(aq)
O ( l) H
+
-
HC N ( aq ) + H
O
( aq ) + CN
(a q)
b)
e)
2
3
3
2
3
+
-
c) H
S(aq) +H
O(l)
H
O
(aq) +HS
(aq)
2
2
3
Solution
+
-
a)
HBr (aq) + H
O (l)
H
O
(aq) + Br
(aq)
2
3
acid
base
acid
base
-
-
b)
H
O (l) + N
(aq)
NH
(aq) + OH
(aq)
2
3
3
acid
base
acid
base
+
-
c)
H
S (aq) + H
O (l)
H
O
(aq) + HS
(aq)
2
2
3
acid
base
acid
base
2 -
-
-
d)
SO
(aq) + H
O (l)
HSO
(aq) + OH
(aq)
3
2
3
base
acid
acid
base
+
-
e)
HCN (aq) + H
O (l)
H
O
(aq) + CN
(aq)
2
3
acid
base
acid
base
9.7
Identify each conjugate acid-base pair in the equations for Exercise 9.5
Solution
Acid
Conjugate Base
Base
Conjugate Acid
-
+
a)
HBr
Br
H
O
H
O
2
3
-
-
b)
H
O
OH
N
HN
2
3
3
-
+
c)
H
S
HS
H
O
H
O
2
2
3
-
2 -
-
d)
H
O
OH
SO
HSO
2
3
3
-
+
e)
HCN
CN
H
O
H
O
2
3