2/14/2016
What’s your favorite Girl Scout
Cookie?
A.
B.
C.
D.
E.
F.
Samoas/Carmel Delight
Thin Mint
Tagalong/Peanut Butter Patty
Savannah/Peanut Butter Sandwich
Trefoil/Shortbread
Thanks-a lot/shortbread
w/choc.fudge
ht int ..
on fan
.
ad ...
.
m
li g M
r. .
re
d
G. Lemon
Le kie
De hin tter utte rtb re a
o
el
u
T
B
ho
tb
co
rm
t B nut il/S hor
a
a
u
t
C
fo t/s
an
ea
No
s/
H. Not a cookie fan
Pe h/P Tre lo
oa
g/
-a
a
m
Sa
Ta
A.
B.
C.
D.
E.
[H2CO3] > [HCO3-] and [H2PO4-] > [HPO42-]
[H2CO3] = [HCO3-] and [H2PO4-] > [HPO42-]
[H2CO3] = [HCO3-] and [HPO4-] > [H2PO4-]
[HCO3-] > [H2CO3] and [HPO42-] > [H2PO4-]
[H2CO3] > [HCO3-] and [HPO42-] > [H2PO4-]
20% 20% 20% 20% 20%
O
2C
[H
>
3]
CO
[H
3-]
O
2C
[H
an
d
=
3]
[. ..
[. ..
[. ..
[. ..
[. ..
d
d
d
nd
an
an
an
]a
3-]
3-]
O3
CO
CO
2C
[H
= [H
> [H
>
3]
-]
3]
3
O
O
2C
CO
2C
[H
[H
[H
CO
[H
3-]
Consider a solution of 2.0 M HCN and 1.0 M
NaCN (Ka for HCN = 6.2 x 10-10). Which of the
following statements is true?
se
.
ar
e
ov
e
m
be
ab
ill
ft
he
lo
Al
w
fa
l
.. .
or
er
>[
7.
0.
..
be
is
be
n
ill
tio
w
ol
u
H
ep
es
Th
H+
]
20% 20% 20% 20% 20%
no
ta
A. The solution is not a buffer
because [HCN] is not equal to
[CN-].
B. The pH will be below 7.00
because the concentration of the
acid is greater than that of the
base.
C. [OH-] > [H+]
D. The buffer will be more resistant
to pH changes from addition of
strong acid than of strong base.
E. All of the above are false.
Th
th
e
se
2.
84
of
No
ne
3.
02
3.
32
s
[O
H]
20%
k
an
uf
fe
r
20%
Th
eb
20%
3.14
3.32
3.02
2.84
None of these
3.
14
A.
B.
C.
D.
E.
20%
nn
Th
20%
va
Sa
bu
f..
.
Calculate the pH of a solution that is
2.00 M HF, 1.00 M NaOH, and 0.500 M
NaF. (Ka = 7.2 x 10-4)
on
Consider a solution consisting of the following two
buffer systems:
H2CO3  HCO3- + H+ pKa = 6.4
H2PO4-  HPO42- + H+ pKa = 7.2
At a pH of 6.4, which of the following statements is
correct?
Which of the following will not
produce a buffer solution?
A. 100 mL of 0.10 M Na2CO3
20% 20% 20% 20% 20%
and 50 mL of 0.1 M HCl
B. 100 mL of 0.10 M NaHCO3
and 25 mL of 0.2 M HCl
C. 100 mL of 0.10 M Na2CO3
and 75 mL of 0.2 M HCl
D. 50 mL of 0.20 M Na2CO3
..
..
..
..
. ..
O.
O.
O.
O.
O3
2C
2C
2C
HC
and 5 mL of 1.0 M HCl
2C
Na
Na
Na
Na
Na
M
M
M
M
M
0
0
0
10
1
1
0
1
.
.
.
E. 100 mL of 0.10 M Na2CO3 mL of 0 mL of 0. mL of 0 L of 0.2 mL of 0
m
0
0
0
0
and 50 mL of 0.1 M NaOH10 10 10 50 10
l
ga
lo
w
Ch. 15 Review
13% 13% 13% 13% 13% 13% 13% 13%
1
2/14/2016
If 25.0 mL of 0.451 M NaOH solution is titrated
with 0.253 M H2SO4, the flask at the endpoint
will contain (besides the indicator
phenolphthalein) as the principal components:
20% 20% 20% 20% 20%
A. Sodium hydroxide, sulfuric
acid, and water
B. Dissolved sodium sulfate
and water
C. Sodium hydroxide,
sodium sulfate, and water
D. Dissolved sodium sulfate,
sulfuric acid , and water
E. Precipitated sodium
sulfate and water
di
So
um
hy
id
ox
dr
ss
Di
e,
v
ol
lf
su
ed
..
ur
di
so
um
di
So
l
su
um
.
te
fa
hy
..
id
ox
dr
ss
Di
e,
u
di
so
v
ol
ed
...
di
so
um
ec
Pr
l
su
.
,. .
te
fa
it a
ip
d
te
u
di
so
m
lfa
su
A 10.-mL sample of tartaric acid is titrated
to a phenolphthalein endpoint with 20.mL
of 1.0 M NaOH. Assuming tartaric acid is
diprotic, what is the molarity of the acid?
A.
B.
C.
D.
E.
..
2.0
1.0
4.0
10.
Impossible to
determine
20% 20% 20% 20% 20%
0
2.
0
1.
.
10
0
4.
i
ss
po
e
bl
to
de
r
te
m
in
e
Im
A student titrates an unknown weak acid, HA, to
a pale pink phenolpthalein endpoint with 30.0
mL of 0.100 M NaOH. The student then adds
12.0 mL of 0.100 M HCl. The pH of the resulting
solution is 5.2. Which of the following is true?
20%
20%
20%
20%
0.20 mol
1.20 mol
1.00 x 10-13
1.50 mol
None of these
20
0.
ol
m
ol
20
1.
m
00
1.
ol
13
0x1
50
1.
se
m
ne
No
of
20% 20% 20% 20% 20%
A. At pH 5.2, half the conjugate
base, A-, has been converted
to HA.
B. The pKa of the acid is 5.2.
C. The pKa of the acid is less
than 5.2
D. The pKa of the acid is greater
than 5.2
E. More than one of the above
is correct.
e
th
At
pH
2,
5.
l
ha
f
e
th
Th
co
ep
..
u.
nj
Ka
of
e
th
Th
ac
ep
id
Ka
is
o
2.
5.
he
ft
Th
ac
ep
id
Ka
is
of
.
s..
le
ac
e
th
id
e
or
is
e
gr
an
th
.. .
e
on
of
th
ea
..
b.
M
Consider the following information about the diprotic acid, H 2X.
H2X  H+ + HXKa1 = 7.9 x 10-5
pKa = 4.10
HX-  H+ + X2Ka1 = 1.6 x 10-12
pKa = 11.79
The titration curve for Na2X, with standard HCl is shown below.
Consider the following information about the diprotic acid, H2X.
H2X  H+ + HXKa1 = 7.9 x 10-5
pKa = 4.10
HX-  H+ + X2Ka1 = 1.6 x 10-12
pKa = 11.79
The titration curve for Na2X, with standard HCl is shown below.
What major species is (are) present at point III?
What is the pH at point I (V1/2 HCl added)?
20%
4.1
H+
an
d
H2
X
ly
on
ly
H2
X
d
an
H2
X
HX
nd
HX
-
on
HX
-
20%
20%
20%
20%
of
20%
No
ne
20%
5
20%
12
.3
9
20%
4.10
7.95
11.79
12.39
None of these
0
20%
A.
B.
C.
D.
E.
7.9
and
HX- only
HX- and H2X
H2X only
H2X and H+
11
.7
9
HX-
X2
-a
A.
B.
C.
D.
E.
X2-
ese
20%
A.
B.
C.
D.
E.
th
What quantity of NaOH(s) must be added
to 2.00 L of 0.500 M HCl to achieve a pH of
13.00? (Assume no volume change.)
2
2/14/2016
Consider the following information about the diprotic acid, H 2X.
H2X  H+ + HXKa1 = 7.9 x 10-5
pKa = 4.10
HX-  H+ + X2Ka1 = 1.6 x 10-12
pKa = 11.79
The titration curve for Na2X, with standard HCl is shown below.
Consider the following information about the diprotic acid, H2X.
H2X  H+ + HXKa1 = 7.9 x 10-5
pKa = 4.10
HX-  H+ + X2Ka1 = 1.6 x 10-12
pKa = 11.79
The titration curve for Na2X, with standard HCl is shown below.
What is the pH at point III?
Which of the following is a major species present at point IV?
A.
B.
C.
D.
E.
A.
B.
C.
D.
E.
4.10
7.95
11.79
12.39
None of these
20%
20%
20%
20%
20%
H2X
HXX2H+
None of these
20%
20%
ese
of
A.
B.
C.
D.
E.
Indicator A, Ka = 10-14
Indicator B, Ka = 10-11
Indicator C, Ka = 10-8
Indicator D, Ka = 10-6
None of these
ca
di
In
=
4
-1
10
,K
c
di
In
c
di
In
or
at
C,
Ka
=1
8
0-
c
di
In
K
D,
or
at
a=
se
-6
10
ne
No
of
e
th
-d
).
se
(a
.. .
ut
.. .
ed
of
th
e
in
er
m
de
t
No
ne
ut
i..
so
l
ed
bu
ffe
r
no
t
Ca
n
of
be
ut
i..
so
l
so
l
ed
ed
bu
ffe
r
of
of
H
H
ep
ep
Th
bu
ffe
r
n.
in
fo
rm
at
io
.
ue
.
bl
1
-1
10
20% 20% 20% 20% 20%
no
ug
h
The pH of buffered solution 1 is
greater than that of buffered
solution 2.
B. The pH of buffered solution 2 is
greater than that of buffered
solution 1.
C. The pH of buffered solution 1 is
equal to that of buffered solution
2.
D. Cannot be determined without
the Ka values.
E. None of these (a-d).
No
te
ge
.
llo
w
e
th
You have two buffered solutions. Buffered
solution 1 consists of 5.0 M HOAc and 5.0 M
NaOAc; buffered solution 2 is made of 0.050 M
HOAc and .050 M NaOAc.
A.
ye
a=
B
or
at
H
20% 20% 20% 20% 20%
re
d.
red.
orange.
yellow.
blue.
Not enough
information.
or
an
A.
B.
C.
D.
E.
Ka
ep
Methyl orange is an indicator with a Ka of 1 x 10-4.
Its acid form, Hin, is red, while its base form, In-, is
yellow. At pH 6.0, the indicator will be
to
,
rA
Th
HNO2 + K+ OH-  KNO2 + H2O
HNO2 + H2O  NO2- + H3O+
HNO2 + KOH  K+ + NO2- + H2O
HNO2 + OH-  NO2- + H2O
H+ + OH-  H2O
of
In the titration of a weak acid HA with 0.100 M
NaOH the stoichiometric point is known to occur
at a pH value of approximately 10. Which of the
following indicator acids would be
20%best
20% to
20% use
20% to
20%
mark the endpoint of this titration?
Th
A.
B.
C.
D.
E.
se
ne
No
No
ne
Which of the following is the net ionic equation
for the reaction that occurs during the titration
of nitrous acid with potassium hydroxide?
20%
H+
th
5
12
.3
9
0
7.9
11
.7
9
20%
X2
HX
X
H2
4.1
20%
3
2/14/2016
You have two buffered solutions. Buffered
solution 1 consists of 5.0 M HOAc and 5.0 M
NaOAc; buffered solution 2 is made of 0.050 M
HOAc and .050 M NaOAc.
True/False: Buffered solution 1 has a greater
buffering capacity than buffered solution
2.50%
50%
A. True
B. False
Tr
ue
ls
Fa
The two salts AgX and AgY have very similar solubilities
in water. It is known that the salt AgX is much more
solube in acid than is AgY. What can be said about the
relative strengths of the acids HX and HY?
20% 20% 20% 20% 20%
A.
B.
C.
D.
Nothing
HY is stronger than HX.
HX is stronger than HY.
The acids have equal
strengths.
E. Cannot be
determined.
in
th
No
e
HY
is
st
g
er
ng
ro
a
th
HX
n
.
HX
rt
r
st
is
ge
on
Th
Which of the following compounds is
the most soluble in water?
BaSO4 (Ksp = 1.5 x 10-9)
CoS (Ksp = 5.0 x 10-22)
PbSO4 (Ksp = 1.3 x 10-8)
AgBr (Ksp = 5.0 x 10-13)
25% 25% 25% 25%
Ba
4
SO
(K
sp
=
5
1.
9)
0x1
S
Co
(K
sp
.0
=5
)
22
0x1
4
SO
Pb
(K
sp
.3
=1
8)
0x1
p
Ks
.0
=5
A.
B.
C.
D.
E.
Al(OH)3 (Ksp = 2 x 10-32)
CdS (Ksp = 1.0 x 10-28)
PbSO4 (Ksp = 1.3 x 10-8)
Sn(OH)2 (Ksp = 3 x 10-27)
MgC2O4 (Ksp = 8.6 x 10-5)
e
av
eq
.
r..
st
l
ua
n
Ca
t
no
in
t
de
be
ed
.
m
er
20% 20% 20% 20% 20%
)
13
0x1
(
Br
Ag
Al
H)
(O
3(
p
Ks
=2
)
32
0x1
)
28
0x1
sp
p
Ks
S
Cd
(K
.0
=1
4
SO
Pb
(
8)
0x1
.3
=1
(O
Sn
2
H)
(
p
Ks
=
3x
7)
-2
10
4
2O
gC
sp
(K
=
6
8.
5)
0x1
M
Given the following Ksp values
PbCrO4 Ksp = 2.0 x 10-16
Zn(OH)2 Ksp = 4.5 x 10-17
Pb(OH)2 Ksp = 1.2 x 10-15
MnS Ksp = 2.3 x 10-13
which statement about solubility in mol/L in water is
20% 20% 20% 20% 20%
correct?
If the dissolving of an ionic solid is
exothermic, which of the following
statements is correct?
33% 33% 33%
A. Heating the water will
increase the solubility of
the ionic solid.
B. Cooling the water will
increase the solubility of
the ionic solid.
C. The temperature of the
water does not affect the
solubility of the ionic solid.
sh
c id
.
HY
Which of the following compounds has
the lowest solubility in water?
A.
PbCrO4, Zn(OH)2, and Pb(OH)2 have
equal solubilities in water.
Zn(OH)2 has the lowest solubility in
water.
C. The solubility of MnS is pH dependent.
D. MnS has the highest molar solubility in
water.
E. A saturated PbCrO4 solution will have
a higher [Pb2+] than a saturated
Pb(OH)2 solution.
..
st
m
ola
Pb
...
Cr
O4
so
lu
. ..
...
is
nS
ed
hig
he
tu
ra
t
th
e
ha
s
sa
nS
A
P..
.
es
ts
nd
w
lo
yo
fM
bil
it
olu
M
H)
2,
a
th
e
n(
O
ha
s
H)
2
es
Th
at
Th
et
em
pe
r
he
lin
gt
Pb
Cr
O4
,Z
...
of
th
e
at
w
w
he
Co
o
t in
gt
He
a
ur
e
er
at
er
w
w
ill
ill
in
in
...
...
B.
Zn
(O
A.
B.
C.
D.
ea
n
ha
4
2/14/2016
Which of the following salts is more
soluble in 1.0 M H+ than in pure
water? (Enter all that apply.)
14%
A.
B.
C.
D.
E.
F.
G.
14%
14%
14%
14%
14%
14%
NaCl
CaCO3
KCl
AgCl
KNO3
MgS
NaCN
A 50.0-mL sample of 0.100 M Ca(NO)3 is mixed with
50.00 mL of 0.200 M NaF. When the system has come
to equilibrium, which of the following sets of conditions
will hold?
Option Moles solid [Ca2+] (M) [F-] (M)
CaF2 formed
A A. A 5.0 x 10-3
3.5 x 10-4 7.0 x 10-4
-3
B.
B
B
5.0 x 10
3.4 x 10-9
0.050
-3
C.
C
C
5.0 x 10
2.2 x 10-4 4.3 x 10-4
D D. D 5.0 x 10-3
3.5 x 10-4 4.3 x 10-4
-3
E E. E10.0 x 10
1.3 x 10-5 1.3x 10-5
20%
Cl
Na
C
Ca
Cl
Ag
l
KC
O3
gS
O3
KN
20%
B
E
20% 20% 20% 20% 20%
Cl
Cu
Cl
Ag
Cl
Au
ld
te
it a
c ip
ou
lw
ill
e
pr
as
n
Ca
e
th
t
no
...
be
in
t
de
ed
.
m
er
In which situation(s) would the concentration of I - in
solution be double the concentration of Pb 2+?
(Enter all that apply.)
in
as
ol
u
ti.
.
at
er
w
ol
u
as
tio
Pb
I2
in
gs
iss
M
Di
ss
ol
v
in
g
ol
u
in
in
Pb
I2
Pb
I2
in
g
ol
v
Di
ss
ol
v
Di
ss
t. .
.
25% 25% 25% 25%
A. Dissolving PbI2 in
water
B. Dissolving PbI2 in a
solution of NaI.
C. Dissolving PbI2 in a
solution of Pb(NO3)2.
D. Missing solutions of
Pb(NO3)2 and KI.
in
g
50%
No
Ye
s
D
of
Pb
(..
.
. ..
CuCl
AgCl
AuCl
All will precipitate as
the same time.
E. Cannot be
determined.
de
c
re
as
e
th
e
. ..
i..
.
ld
wo
u
th
e
ea
se
nc
e
ub
st
a
in
cr
Ei
th
er
s
ld
ou
NH
3w
A.
B.
C.
D.
Al
If 30 mL of 5.0 x 10-4 M Ca(NO3)2 are added 70
mL of 2.0 x a0-4 M NaF, will a precipitate occur?
(Ksp CaF2 = to 4.0 x 10-11)
C
Sodium chloride is added slowly to a solution that is
0.010 M in Cu+, Ag+, and Au+. The Ksp values for the
chloride salts are 1.9 x 10-7, 1.6 x 10-10, and 2.0 x 10-13,
respectively. Which compound will precipitate first?
NH
3w
ea
se
in
cr
ld
ou
rs
th
e
Ei
NH
3w
ub
st
a
nc
e
wo
u
ld
th
e
...
. ..
A.
A. Yes
B. No
20%
ns
Silver acetate (AgC2H3O2) is a sparingly soluble salt with
Ksp = 1.9 x 10-3. Consider a saturated solution in
equilibrium with the solid salt. Compare the effects on
the solubility of adding to the solution either the acid
HNO3 or the base NH3.20% 20% 20% 20% 20%
50%
20%
CN
Na
M
A
Either substance would decrease
solubility.
B. NH3 would increase the solubility,
but HNO3 would decrease it.
C. NH3 would increase the solubility,
but HNO3 would have virtually no
effect.
D. Either substance would increase
the solubility.
E. NH3 would decrease the solubility,
but HNO3 would increase it.
20%
5
2/14/2016
Team Scores
Points
Team
Points
Team
6