Section 18.3
Using Equilibrium Constants
Practice Test
1.
Which of the solubility product expressions is incorrect?
a.
K
sp
(Ag
2
S) = [Ag
+
]
2
[S
2-
]
b.
K
sp
(Sb
2
S
3
) = [Sb
2+
]
3
[S
3-
]
2
c.
K
sp
(CaF
2
) = [Ca
2+
][F
-
]
2
d.
K
sp
(CuS) = [Cu
2+
][S
2-
]
Hint
2.
The molar solubility for BaCO
3
is 9.0 x 10
-5
M
at 25°C. What is the solubility product constant,
K
sp
, for BaCO
3
?
a.
1.2 x 10
-8
b.
8.1 x 10
-9
c.
5.3 x 10
-12
d.
4.0 x 10
-15
Hint
3.
The value of the
K
sp
for SrSO
4
is 2.8 x 10
-7
. What is the molar solubility of SrSO
4
?
a.
7.6 x 10
-7
M
b.
5.8 x 10
-13
M
c.
5.3 x 10
-4
M
d.
5.7 x 10
-3
M
Hint
4.
If NaCl is added to a 0.010M solution of AgNO
3
in water at 25°C, what will be [Cl
-
] when precipitation of AgCl begins? The Ksp for AgCl is 1.8 x 10
-10
.
a.
1.0 x 10
-10
M
b.
1.3 x 10
-6
M
c.
1.8 x 10
-8
M
d.
1.8 x 10
-12
M
Hint
5.
How many grams of MgF
2
will dissolve in 150 mL of 0.100
M
NaF solution? Ksp for MgF
2
is 6.4 x 10
-9
.
a.
6.4 x 10
-7
g
b.
4.1 x 10
-6
g
c.
1.0 x 10
-5
g
d.
6.0 x 10
-6
g
Hint
