136) If solution (1) is a saturated solution of CuS, which of solutions (2)-(4) are saturated?
A) (2)
B) (3)
C) (4)
D) None of these
137) If solution (1) is a saturated solution of CuS, which of solutions (2)-(4) are supersaturated?
A) (2)
B) (3)
C) (4)
D) None of these
The following pictures represent solutions of AgCl, which may also contain ions other than Ag+ and Cl–
which are not shown. Gray spheres represent Ag+ ions and dotted spheres represent Cl– ions.
138) If solution (1) is a saturated solution of AgCl, which of solutions (1)-(4) represents the solution
after a small amount of HCl is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
139) If solution (1) is a saturated solution of AgCl, which of solutions (1)-(4) represents the solution
after a small amount of HNO3 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
140) If solution (1) is a saturated solution of AgCl, which of solutions (1)-(4) represents the solution
after a small amount of AgNO3 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
141) If solution (1) is a saturated solution of AgCl, which of solutions (1)-(4) represents the solution
after a small amount of NH3 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
The following pictures represent solutions of CaCO3, which may also contain ions other than Ca2+ and
CO32- which are not shown. Gray spheres represent Ca2+ ions and unshaded spheres represent CO32-
ions.
142) If solution (1) is a saturated solution of CaCO3, which of solutions (1)-(4) represents the solution
after a small amount of NaOH is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
143) If solution (1) is a saturated solution of CaCO3, which of solutions (1)-(4) represents the solution
after a small amount of HNO3 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
144) If solution (1) is a saturated solution of CaCO3, which of solutions (1)-(4) represents the solution
after a small amount of Ca(NO3)2 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
145) If solution (1) is a saturated solution of CaCO3, which of solutions (1)-(4) represents the solution
after a small amount of K2CO3 is added and equilibrium is restored?
A) (1)
B) (2)
C) (3)
D) (4)
15.2 Algorithmic Questions
1) What is the hydronium ion concentration in a solution prepared by mixing 50.00 mL of 0.10 M HCN
with 50.00 mL of 0.030 M NaCN? Assume that the volumes of the solutions are additive and that
Ka = 4.9 × 10-10 for HCN.
A) 1.5 × 10– 10 M
B) 4.9 × 10-10 M
C) 1.6 × 10– 9 M
D) 7.0 × 10-6 M
2) What is the pH of a solution prepared by mixing 25.00 mL of 0.10 M CH3CO2H with 25.00 mL of
0.0 10 M CH3CO2Na? Assume that the volume of the solutions are additive and that Ka = 1.8 × 10-5
for CH3CO2H.
A) 2.87
B) 3.74
C) 4.7 5
D) 5. 74
3) What is the pH of a solution prepared by mixing 50.00 mL of 0.10 M NH3 with 5.00 mL of 0.10 M
NH4Cl? Assume that the volume of the solutions are additive and that Kb = 1.8 × 10-5 for NH3.
A) 8. 25
B) 10.26
C) 10.25
D) 11.13
4) What is the pH of a solution prepared by mixing 50.00 mL of 0.10 M methylamine, CH3NH2, with
20.00 mL of 0.10 M methylammonium chloride, CH3NH3Cl? Assume that the volume of the solutions
are additive and that Kb = 3.70 × 10-4 for methylamine.
A) 10.17
B) 10.57
C) 10.97
D) 11.78
5) What is the pH of a buffer system prepared by dissolving 10.70 grams of NH4Cl and 25.00 mL of
12 M NH3 in enough water to make 1.000 L of solution? Kb = 1.80 × 10-5 for NH3.
A) 9.08
B) 9.26
C) 9. 43
D) 11. 32
6) What is the [CH3CO2-]/[CH3CO2H] ratio necessary to make a buffer solution with a pH of 4.34?
Ka = 1.8 × 10-5 for CH3CO2H.
A) 0. 39:1
B) 0. 91:1
C) 1. 09:1
D) 2.5:1
7) What volume of 5.00 × 10–3 M HNO3 is needed to titrate 80.00 mL of 5.00 × 10–3 M Ca(OH)2 to
the equivalence point?
A) 10.0 mL
B) 40.0 mL
C) 80.0 mL
D) 160. mL
8) What is the pH of a solution made by mixing 25.00 mL of 0. 100 M HCl with 40.00 mL of 0.100 M
KOH? Assume that the volumes of the solutions are additive.
A) 0.64
B) 1.64
C) 12.36
D) 13.36
9) What is the approximate pH at the equivalence point of a weak acid-strong base titration if 25 mL of
aqueous formic acid requires 29.80 mL of 0.3567 M NaOH? Ka =1.8 × 10-4 for formic acid.
A) 2. 06
B) 5. 48
C) 8. 52
D) 11.94
10) What is the approximate pH at the equivalence point of a weak acid-strong base titration if 25 mL of
aqueous hydrofluoric acid requires 30.00 mL of 0.400 M NaOH? Ka = 6.76 × 10-4 for HF.
A) 1.74
B) 5.75
C) 8.25
D) 12.26
11) Formic acid (HCO2H, Ka = 1.8 × 10-4) is the principal component in the venom of stinging ants.
What is the molarity of a formic acid solution if 25.00 mL of the formic acid solution requires 29.80 mL
of 0.0567 M NaOH to reach the equivalence point?
A) 0.0134 M
B) 0.0 476 M
C) 0.0567 M
D) 0. 0676 M
12) What is the pH of the resulting solution if 25.00 mL of 0.10 M acetic acid is added to 10.00 mL of
0.10 M NaOH? Assume that the volumes of the solutions are additive. Ka = 1.8 × 10-5 for CH3CO2H
A) 9. 43
B) 9.08
C) 4.92
D) 4. 57
37
13) What is the pH of a solution made by mixing 10.00 mL of 0.10 M acetic acid with 10.00 mL of
0.10 M KOH? Assume that the volumes of the solutions are additive. Ka =1.8 × 10-5 for CH3CO2H.
A) 5.28
B) 7.00
C) 8.72
D) 10.02
14) What is the pH of a solution made by mixing 30.00 mL of 0.10 M acetic acid with 50.00 mL of 0.
100 M KOH? Assume that the volumes of the solutions are additive. Ka = 1.8 × 10-5 for CH3CO2H.
A) 8.26
B) 9.26
C) 11.13
D) 12. 40
15) Sodium hypochlorite, NaOCl, is the active ingredient in household bleach. What is the concentration
of hypochlorite ion if 20.00 mL of bleach requires 32.00 mL of 0.500 M HCl to reach the equivalence
point?
A) 0. 300 M
B) 0. 312 M
C) 0. 800 M
D) 1. 30 M
16) What is the pH at the equivalence point of a weak base-strong acid titration if 20.00 mL of NaOCl
requires 28.30 mL of 0. 50 M HCl? Ka = 3.0 × 10-8 for HOCl.
A) 0.30
B) 3. 18
C) 3.76
D) 4. 03
17) What is the pH of the resulting solution if 45 mL of 0.432 M methylamine, CH3NH2, is added to
15 mL of 0.234 M HCl? Assume that the volumes of the solutions are additive. Ka = 2.70 × 10-11 for
CH3NH3+.
A) 2.77
B) 4.09
C) 9.91
D) 11.23
18) Calculate the Ksp for silver sulfite if the solubility of Ag2SO3 in pure water is 4.6 × 10-3 g/L.
A) 3.8 × 10-15
B) 1.5 × 10-14
C) 2.4 × 10-10
D) 4.8 × 10-10
19) Calculate the solubility (in g/L) of silver chromate in water at 25°C if the Ksp for Ag2CrO4 is
1.1 × 10-12.
A) 3.5 × 10-4 g/L
B) 6.5 × 10-5 g/L
C) 2.7 × 10-2 g/L
D) 3.4 × 10-2 g/L
20) What is the molar solubility of Mg(OH)2 in a basic solution with a pH of 12.50? Ksp for Mg(OH)2
is 5.61 × 10-12.
A) 1.8 × 10– 10 M
B) 5.6 × 10– 9 M
C) 2.4 × 10-6 M
D) 1.1 × 10-4 M
21) Calculate the molar solubility of thallium(I) chloride in 0. 40 M NaCl at 25°C. Ksp for TlCl is
1.7 × 10-4.
A) 6.8 × 10-5 M
B) 4.2 × 10– 4 M
C) 8.2 × 10-3 M
D) 1.3 × 10-2 M
22) In which of the following solutions would solid PbBr2 be expected to be the least soluble at 25°C?
A) 0.1 M H Br
B) 0.1 M NaBr
C) 0.1 M CaBr2
D) 0.1 M K NO3
23) What is the molar solubility of AgCl in 0. 20 M NH3? Ksp for AgCl is 1.8 × 10-10 and Kf for
Ag(NH3)2+ is 1.7 × 107.
A) 1.3 × 10-5 M
B) 1.0 × 10– 2 M
C) 1.1 × 10– 2 M
D) 5.5 × 10-2 M
24) What is the molar solubility of AgCl in 0. 10 M NaCN if the colorless complex ion Ag(CN)2–
forms? Ksp for AgCl is 1.8 × 10-10 and Kf for Ag(CN)2– is 1.0 × 1021.
A) 0. 050 M
B) 0. 10 M
C) 0.20 M
D) 0.40 M
25) 0.10 M potassium chromate is slowly added to a solution containing 0. 50 M AgNO3 and 0. 50 M
Ba(NO3)2. What is the Ag+ concentration when BaCrO4 just starts to precipitate? The Ksp for
Ag2CrO4 and BaCrO4 are 1.1 × 10-12 and 1.2 × 10-10, respectively.
A) 6.5 × 10-5 M
B) 1.3 × 10-4 M
C) 3.2 × 10-4 M
D) 6.8 × 10-2 M
15.3 Short Answer Questions
1) The balanced net ionic equation for the neutralization reaction involving equal molar amounts of
HNO3 and KOH is ________.
2) The balanced net ionic equation for the neutralization reaction involving equal molar amounts of
HCl and CH3CH2NH2 is ________.
3) What is the equation relating the equilibrium constant Kn for the neutralization of a weak acid with a
weak base to the Ka of the acid, the Kb of the base and Kw?
4) The neutralization constant Kn for the neutralization of penicillin V (C16H18N2O5S) and
erythromycin (C37H67NO13) is 1.3 × 106. The acid dissociation constant Ka for penicillin V is
2.0 × 10-3. What is the base dissociation constant Kb for erythromycin?
5) The solution formed upon adding 50.00 mL of 0.10 M NH4Cl to 50.00 mL of 0.10 M NH3 will have
a pH that is ________ the pH of the original NH3 solution.
6) The pH of a solution of HIO3 (Ka = 1.7 × 10-1) and KIO3 is 1.00. What is the molarity of KIO3 if
the molarity of HIO3 is 0.025 M?
7) The pH of a solution of ethylamine, C2H5NH2 (Kb = 6.4 × 10-4) and ethylammium bromide,
C2H5NH3Br is 11.00. What is the molarity of C2H5NH3Br if the molarity of C2H5NH2 is 0.025 M?
8) A buffer prepared by mixing 50.00 mL of 0.10 M HF with 50.00 mL of 0.10 M NaF will have a pH
that is ________ 7.0.
9) A buffer prepared by mixing equal moles of an acid having Ka = 4.5 × 10–4 and a salt of its conjugate
base has a pH = ________.
10) The pH of a 0.150 M formic acid/0.250 M sodium formate buffer = ________? The Ka of formic
acid is 1.8 × 10–4.
11) Addition of 0.0125 mol KOH to 150 mL of a 0.150 M formic acid/0.100 M sodium formate buffer
results in a pH = ________? The Ka of formic acid is 1.8 × 10–4.
12) Addition of 0.0125 mol HCl to 150 mL of a 0.150 M formic acid/0.100 M sodium formate buffer
results in a pH = ________? The Ka of formic acid is 1.8 × 10–4.
13) What is the Ka of the amino acid glycine if it is 75.0% dissociated at pH = 10.08?
14) What is the Ka of the amino acid glutamine if it is 33.0% dissociated at pH = 8.82?
15) The addition of ________ mL of 0.1500 M NaOH is required to titrate 25.00 mL of 0.2250 M HCl
to the equivalence point, which occurs at a pH of ________.
16) What is the pH of the solution formed when 50 mL of 0.250 M NaOH is added to 50 mL of 0.120 M
HCl?
17) What is the pH of the solution formed when 25 mL of 0.173 M NaOH is added to 35 mL of 0.342 M
HCl?
18) The half equivalence point in the titration of 0.100 M HCO2H (Ka = 1.8 × 10–4) with 0.250 M
NaOH occurs at pH = ________.
19) The half equivalence point in the titration of 0.100 M CH3NH2 (Kb = 3.7 × 10–4) with 0.250 M
HCl occurs at pH = ________.
20) Selenous acid, H2SeO3 has acid dissociation constants Ka1 = 3.5 × 10–2 and Ka2 = 5 × 10–8. When
25.00 mL of 0.100 M selenous acid is titrated with 0.200 M NaOH the first equivalence point occurs at
pH = ________.
21) At 25°C calcium fluoride has a solubility product constant Ksp = 3.5 × 10–11. The solubility of
CaF2 at this temperature is ________ mol/L.
22) Silver oxalate, Ag2C2O4, has a molar solubility = 1.1 × 10-4 mol/L. Ag2C2O4 has a solubility
product Ksp = ________.
23) The artist’s pigment cadmium yellow, CdS, has a water solubility of 0.13 g/L. The solubility product
of CdS, Ksp = ________.
24) State whether the solubility of Cu(OH)2 will increase or decrease upon the addition of aqueous
solutions of a) HCl, b) NaOH, c) NH3.
25) CaF2 has Ksp = 3.5 × 10-11. If 25 mL of 8.0 × 10-4 M Ca(NO3)2 is mixed with 75 mL of
4.0 × 10-4 M KF, a precipitate of CaF2 ________ (will, will not) form.