Deck 16: Acid-Base Equilibria and Solubility Equilibria

Question 1

You are asked to go into the lab and prepare an acetic acid - sodium acetate buffer solution with a pH of 4.00 $\pm$ 0.02. What molar ratio of CH₃COOH to CH₃COONa should be used

A) 0.18
B) 0.84
C) 1.19
D) 5.50
E) 0.10

Answer 1

5.50

Question 2

In which one of the following solutions will acetic acid have the greatest percent ionization

A) 0.1 M CH₃COOH
B) 0.1 M CH₃COOH dissolved in 1.0 M HCl
C) 0.1 M CH₃COOH plus 0.1 M CH₃COONa
D) 0.1 M CH₃COOH plus 0.2 M CH₃COONa

Answer 2

0.1 M CH₃COOH

Question 3

Consider a buffer solution prepared from HOCl and NaOCl. Which is the net ionic equation for the reaction that occurs when NaOH is added to this buffer

A)OH^- + HOCl $\rarr$ H₂O + OCl^-
B)OH^- + OCl^- $\rarr$ HOCl + O^2-
C)Na⁺ + HOCl $\rarr$ NaCl + OH^-
D)H⁺ + HOCl $\rarr$ H₂ + OCl^-
E)NaOH + HOCl $\rarr$ H₂O + NaCl

Answer 3

OH^- + HOCl $\rarr$ H₂O + OCl^-

Question 4

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed

A) 0.050 M H₃PO₄ and 0.050M HCl
B) 0.050M H₃PO₄ and 0.025 M HCl
C) 0.050M NaH₂PO₄ and 0.025M NaOH
D) 0.050M Na₃PO₄ and 0.050M M NaOH
E) 0.050M Na₃PO₄ and 0.025M NaOH

Question 5

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer solution with an optimum pH of 4.6-4.8

A) CH₃COO₂Na / CH₃COOH (K_a = 1.8 * 10^-5)
B) NH₃ / NH₄Cl (K_a = 5.6 *10^-10)
C) NaOCl / HOCl (K_a = 3.2 * 10^-8)
D) NaNO₂ / HNO₂ (K_a = 4.5 * 10^-4)
E) NaCl / HCl

Question 6

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed

A) 0.10M HCl and 0.10 M NaCl
B) 0.15 M HNO₃ and 0.15 M NaNO₃
C) 0.10M HF and 0.10M NaF
D) 0.10M HClO₄ and 0.10 NaClO₄
E) 0.15M HBr and 0.15M NaBr

Question 7

Calculate the pH of a solution that is 0.410 M in HOCl and 0.050 M in NaOCl. [K_a(HOCl) = 3.2 * 10^-8]

A) 0.39
B) 3.94
C) 6.58
D) 7.49
E) 8.40

Question 8

Which one of the following combinations cannot function as a buffer solution

A) HCN and KCN
B) NH₃ and (NH₄)₂SO₄
C) HNO₃ and NaNO₃
D) HF and NaF
E) HNO₂ and NaNO₂

Question 9

A solution is prepared by mixing 500. mL of 0.10 M NaOCl and 500. mL of 0.20 M HOCl. What is the pH of this solution
[K_a(HOCl) = 3.2 * 10^-8]

A) 4.10
B) 7.00
C) 7.19
D) 7.49
E) 7.80

Question 10

Calculate the pH of a buffer solution that contains 0.25 M benzoic acid (C₆H₅CO₂H) and 0.15M sodium benzoate (C₆H₅COONa). [K_a = 6.5 * 10^-5 for benzoic acid]

A) 3.97
B) 4.83
C) 4.19
D) 3.40
E) 4.41

Question 11

Which one of the following is a buffer solution

A) 0.40 M HCN and 0.10 KCN
B) 0.20 M CH₃COOH
C) 1.0 M HNO₃ and 1.0 M NaNO₃
D) 0.10 M KCN
E) 0.50 M HCl and 0.10 NaCl

Question 12

Calculate the pH of a buffer solution prepared by dissolving 0.2 mole of sodium cyanate (NaCNO) and 1.0 mole of cyanic acid (HCNO) in enough water to make 1.0 liter of solution. [K_a(HCNO) = 2.0 * 10^-4]

A) 0
B) 3.0
C) 3.7
D) 4.4
E) 5.0

Question 13

What is the net ionic equation for the reaction that occurs when small amounts of hydrochloric acid are added to a HOCl/NaOCl buffer solution

A)H⁺ + H₂O $\rarr$ H₃O⁺
B)H⁺ + OCl^- $\rarr$ HOCl
C)HOCl $\rarr$ H⁺ + OCl^-
D)H⁺ + HOCl $\rarr$ H₂OCl⁺
E)HCl + HOCl $\rarr$ H₂O + Cl₂

Question 14

Within what pH range is a HOCl - NaOCl buffer effective

A) pH 2.0 - pH 4.0
B) pH 7.5 - pH 9.5
C) pH 6.5 - pH 8.5
D) pH 6.5 - pH 9.5
E) pH 1.0 - pH 14.0

Question 15

Which of the following is the most acidic solution

A) 0.10 M CH₃COOH and 0.10 M CH₃COONa
B) 0.10 M CH₃COOH
C) 0.10 M HNO₂
D) 0.10 M HNO₂ and 0.10 M NaNO₂
E) 0.10 M CH₃COONa

Question 16

Calculate the pH of a buffer solution prepared by dissolving 0.20 mole of cyanic acid (HCNO) and 0.80 mole of sodium cyanate (NaCNO) in enough water to make 1.0 liter of solution.[K_a(HCNO) = 2.0 * 10^-4]

A) 0.97
B) 3.10
C) 4.40
D) 3.70
E) 4.30

Question 17

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed

A) 0.10M H₂CO₃ and 0.050M HCl
B) 0.10M H₂CO₃ and 0.10M KOH
C) 0.10M H₂CO₃ and 0.10M HCl
D) 0.10M H₂CO₃ and 0.050M KOH
E) 0.10M K₂CO₃ and 0.050M KOH

Question 18

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer solution with an optimum pH of 9.2-9.3

A) CH₃COONa / CH₃COOH (K_a = 1.8 * 10^-5)
B) NH₃ / NH₄Cl (K_a = 5.6 * 10^-10)
C) NaOCl / HOCl (K_a = 3.2 * 10^-8)
D) NaNO₂ / HNO₂ (K_a = 4.5 * 10^-4)
E) NaCl / HCl

Question 19

You have 500.0 mL of a buffer solution containing 0.20 M acetic acid (CH₃COOH) and 0.30 M sodium acetate (CH₃COONa). What will the pH of this solution be after the addition of 20.0 mL of 1.00 M NaOH solution [K_a = 1.8 * 10^-5]

A) 4.41
B) 4.74
C) 4.56
D) 4.92
E) 5.07

Question 20

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed

A) 0.10 M NH₃ and 0.10 M HCl
B) 0.10 M NH₄⁺ and 0.10 M KOH
C) 0.20 M NH₃ 0.10 M KOH
D) 0.20 M NH₃ and 0.10 M HCl
E) 0.20 M NH₄⁺ and 0.10M HCl

Question 21

For which type of titration will the pH be basic at the equivalence point

A) Strong acid vs. strong base.
B) Strong acid vs. weak base.
C) Weak acid vs. strong base.
D) All of the above.
E) None of the above.

Question 22

Acid dissociation constants for phosphoric acid are given below. $\begin{array}{|l|l|l|l|}\hline & \mathrm{K}_{\mathrm{a} 1} & \mathrm{~K}_{\mathrm{a} 2} & \mathrm{~K}_{\mathrm{a} 3} \\\hline \mathrm{H}_{3} \mathrm{PO}_{4} & 7.5 \times 10^{-3} & 6.2 \times 10^{-8} & 4.8 \times 10^{-13} \\\hline\end{array}$ A buffer with a pH = 7.4 can best be made by using

A) H₃PO₄ and NaH₂PO₄.
B) NaH₂PO₄ and Na₂HPO₄.
C) Na₂HPO₄ and Na₃PO₄.
D) only NaH₂PO₄.
E) only Na₂HPO₄.

Question 23

24.00 mL of a 0.25 M NaOH solution is titrated with 0.10M HCl. What is the pH of the solution after 24.00 mL of the HCl has been added

A) 13.40
B) 13.17
C) 11.56
D) 12.88
E) 7.00

Question 24

Calculate the percent ionization of cyanic acid, K_a = 2.0 * 10^-4, in a buffer solution that is 0.50 M HCNO and 0.10 M NaCNO.

A) 0.02%
B) 0.10%
C) 0.20%
D) 2.0%
E) 20%

Question 25

25.0 mL of a 0.100 M solution of NH₃ is titrated with 0.150M HCl. After 10.0 mL of the HCl has been added, the resultant solution is:

A) Basic and before the equivalence point
B) Basic and after the equivalence point
C) Acidic and before the equivalence point
D) Acidic and after the equivalence point
E) Neutral and at the equivalence point

Question 26

For which type of titration will the pH be neutral at the equivalence point

A) Strong acid vs. strong base.
B) Strong acid vs. weak base.
C) Weak acid vs. strong base.
D) All of the above.
E) None of the above.

Question 27

The pH at the equivalence point of a titration may differ from 7.0 due to

A) the initial concentration of the standard solution.
B) the indicator used.
C) the self-ionization of H₂O.
D) the initial pH of the unknown.
E) hydrolysis of the salt formed.

Question 28

Starting with 0.750L of a buffer solution containing 0.30 M benzoic acid (C₆H₅COOH) and 0.35 M sodium benzoate (C₆H₅COONa), what will the pH of the solution be after the addition of 340.0 mL of 0.350M HCl (K_a (C₆H₅COOH) = 6.5 x 10^-5)

A) 4.19
B) 4.25
C) 3.81
D) 0.45
E) 6.54

Question 29

25.0 mL of a 0.100 M solution of NH₃ is titrated with 0.250M HCl. After 25.0 mL of the HCl has been added, the resultant solution is:

A) Basic and before the equivalence point
B) Basic and after the equivalence point
C) Acidic and before the equivalence point
D) Acidic and after the equivalence point
E) Neutral and at the equivalence point

Question 30

Starting with 0.250L of a buffer solution containing 0.250 M benzoic acid (C₆H₅COOH) and 0.20 M sodium benzoate (C₆H₅COONa), what will the pH of the solution be after the addition of 25.0 mL of 0.100M HCl (K_a (C₆H₅COOH) = 6.5 x 10^-5)

A) 4.19
B) 4.10
C) 4.28
D) 4.05
E) 3.78

Question 31

35.0 mL of a 0.250 M solution of KOH is titrated with 0.150 M HCl. After 35.0 mL of the HCl has been added, the resultant solution is:

A) Basic and before the equivalence point
B) Basic and after the equivalence point
C) Acidic and before the equivalence point
D) Acidic and after the equivalence point
E) Neutral and at the equivalence point

Question 32

50.00 mL of 0.10 M HNO₂ (nitrous acid, K_a = 4.5 * 10^-4) is titrated with a 0.10 M KOH solution. After 25.00 mL of the KOH solution is added, the pH in the titration flask will be

A) 2.17.
B) 3.35.
C) 2.41.
D) 1.48.
E) 7.00.

Question 33

A titration of an acid and base to the equivalence point results in a noticeably acidic solution. It is likely this titration involves

A) a strong acid and a weak base.
B) a weak acid and a strong base.
C) a weak acid and a weak base (where K_a equals K_b).
D) a strong acid and a strong base.

Question 34

You have 500.0 mL of a buffer solution containing 0.30 M acetic acid (CH₃COOH) and 0.20 M sodium acetate (CH₃COONa). What will the pH of this solution be after the addition of 20.0 mL of 1.00 M NaOH solution [K_a = 1.8 * 10^-5]

A) 4.65
B) 4.71
C) 4.56
D) 4.84
E) 5.07

Question 35

40.0 mL of a 0.65 M solution of HF is titrated with 0.100 M NaOH. After 0.400 L of the NaOH solution has been added, the resultant solution is:

A) Basic and before the equivalence point
B) Basic and after the equivalence point
C) Acidic and before the equivalence point
D) Acidic and after the equivalence point
E) Neutral and at the equivalence point

Question 36

Calculate the pH at the equivalence point for the titration of 0.20 M HCl with 0.20 M NH₃ (K_b = 1.8 * 10^-5).

A) 2.87
B) 4.98
C) 5.12
D) 7.00
E) 11.12

Question 37

In which one of the following solutions will acetic acid have the greatest percent ionization

A) 0.1 M CH₃COOH
B) 0.1 M CH₃COOH dissolved in 0.1 M HCl
C) 0.1 M CH₃COOH dissolved in 0.2 M HCl
D) 0.1 M CH₃COOH plus 0.1 M CH₃COONa
E) 0.1 M CH₃COOH plus 0.2 M CH₃COONa

Question 38

What is the pH at the equivalence point in the titration of 100 mL of 0.10 M HCl with 0.10 M NaOH

A) 1.0
B) 6.0
C) 7.0
D) 8.0
E) 13.0

Question 39

35.00 mL of a 0.30 M HCl solution is titrated with 0.35 M NaOH. What is the pH of the solution after 40.00 mL of the NaOH has been added

A) 2.46
B) 11.54
C) 7.00
D) 12.72
E) 12.67

Question 40

25.0 mL of a 0.100 M solution of NH₃ is titrated with 0.250M HCl. After 10.0 mL of the HCl has been added, the resultant solution is:

A) Basic and before the equivalence point
B) Basic and after the equivalence point
C) Acidic and before the equivalence point
D) Basic and at the equivalence point
E) Acidic and at the equivalence point

Question 41

The solubility product for barium sulfate is 1.1 * 10^-10. Calculate the molar solubility of barium sulfate.

A) 5.5 * 10^-11 mol/L
B) 1.1 * 10^-5 mol/L
C) 2.1 * 10^-5 mol/L
D) 1.1 * 10^-10 mol/L
E) 2.2 * 10^-10 mol/L

Question 42

Calculate the pH of the solution resulting from the addition of 10.0 mL of 0.10 M NaOH to 50.0 mL of 0.10 M HCN (K_a = 4.9 * 10^-10) solution.

A) 5.15
B) 8.71
C) 5.85
D) 9.91
E) 13.0

Question 43

What is the pH at the equivalence point in the titration of 100 mL of 0.10 M HCN (K_a = 4.9 * 10^-10) with 0.10 M NaOH

A) 3.0
B) 6.0
C) 7.0
D) 11.0
E) 12.0

Question 44

For PbCl₂ (K_sp = 2.4 * 10^-4), will a precipitate of PbCl₂ form when 0.10 L of 3.0 * 10^-2 M Pb(NO₃)₂ is added to 400 mL of 9.0 * 10^-2 M NaCl

A)Yes, because Q > K_sp.
B) No, because Q < K_sp.
C) No, because Q = K_sp
D) Yes, because Q < K_sp.

Question 45

The molar solubility of tin(II) iodide is 1.28 * 10^-2 mol/L. What is K_sp for this compound

A) 8.4 * 10^-6
B) 1.28 * 10^-2
C) 4.2 * 10^-6
D) 1.6 * 10^-4
E) 2.1 * 10^-6

Question 46

What mass of ammonium nitrate must be added to 350. mL of a 0.150 M solution of ammonia to give a buffer having a pH of 9.00
(K_b(NH₃) = 1.8 * 10^-5)

A) 7.6 g
B) 2.4 g
C) 5.4 g
D) 11 g
E) 3.3 g

Question 47

Methyl red is a common acid-base indicator. It has a K_a equal to 6.3 * 10^-6. Its un-ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8

A) green
B) red
C) blue
D) yellow
E) violet

Question 48

The solubility of strontium carbonate is 0.0011 g/100 mL at 20ºC. Calculate the K_sp value for this compound.

A) 7.5 * 10^-5
B) 1.5 * 10^-4
C) 5.6 * 10^-9
D) 7.5 * 10^-6
E) 1.5 * 10^-3

Question 49

The K_sp for silver(I) phosphate is 1.8 * 10^-18. Calculate the molar solubility of silver(I) phosphate.

A) 1.6 * 10^-5 M
B) 2.1 * 10^-5 M
C) 3.7 * 10^-5 M
D) 7.2 * 10^-1 M
E) 1.8 * 10^-1 M

Question 50

Calculate the pH of the solution resulting from the addition of 75.0 mL of 0.15 M KOH to 35.0 mL of 0.20 M HCN (K_a (HCN) = 4.9 * 10^-10).

A) 9.31
B) 9.18
C) 9.52
D) 11.63
E) 12.59

Question 51

The molar solubility of manganese(II) carbonate is 4.2 * 10^-6 M. What is K_sp for this compound

A) 4.2 * 10^-6
B) 8.4 * 10^-6
C) 3.0 * 10^-16
D) 1.8 * 10^-11
E) 2.0 * 10^-3

Question 52

The molar solubility of lead(II) iodate in water is 4.0 * 10^-5 mol/L. Calculate K_sp for lead(II) iodate.

A) 1.6 * 10^-9
B) 6.4 * 10^-14
C) 2.6 * 10^-13
D) 4.0 * 10^-5
E) 4.0 * 10^-15

Question 53

The solubility product for chromium(III) fluoride is K_sp = 6.6 * 10^-11. What is the molar solubility of chromium(III) fluoride

A) 1.6 * 10^-3 M
B) 1.2 * 10^-3 M
C) 6.6 * 10^-11 M
D) 2.2 * 10^-3 M
E) 1.6 * 10^-6 M

Question 54

25.0 mL of a hydrofluoric acid solution of unknown concentration is titrated with 0.200 M NaOH. After 20.0 mL of the base solution has been added, the pH in the titration flask is 3.00. What was the concentration of the original hydrofluoric acid solution. [K_a(HF) = 7.1 * 10^-4]

A) 0.39 M
B) 0.27 M
C) 0.16 M
D) 2.4 M
E) 0.23 M

Question 55

Calculate the pH of the solution resulting from the addition of 25.0 mL of 0.20 M HCl to 50.0 mL of 0.10 M aniline (C₆H₅NH₂). K_b (C₆H₅NH₂) = 3.8 x 10^-10

A) 9.42
B) 9.12
C) 7.00
D) 2.30
E) 2.88

Question 56

The molar solubility of magnesium carbonate is 1.8 * 10^-4 mol/L. What is K_sp for this compound

A) 1.8 * 10^-4
B) 3.6 * 10^-4
C) 1.3 * 10^-7
D) 3.2 * 10^-8
E) 2.8 * 10^-14

Question 57

The solubility of lead(II) iodide is 0.064 g/100 mL at 20ºC. What is the solubility product for lead(II) iodide

A) 1.1 * 10^-8
B) 3.9 * 10^-6
C) 1.1 * 10^-11
D) 2.7 * 10^-12
E) 1.4 * 10^-3

Question 58

What mass of sodium fluoride must be added to 250. mL of a 0.100 M HF solution to give a buffer solution having a pH of 3.50 [K_a(HF) = 7.1* 10^-4]

A) 0.49 g
B) 1.5 g
C) 3.4 g
D) 2.3 g
E) 0.75 g

Question 59

Calculate the pH of the solution resulting from the addition of 85.0 mL of 0.35 M HCl to 30.0 mL of 0.40 M aniline (C₆H₅NH₂). K_b (C₆H₅NH₂) = 3.8 x 10^-10

A) 1.75
B) 0.81
C) 4.64
D) 4.19
E) 9.09

Question 60

40.0 ml of an acetic acid of unknown concentration is titrated with 0.100 M NaOH. After 20.0 mL of the base solution has been added, the pH in the titration flask is 5.10. What was the concentration of the original acetic acid solution? [K_a(CH₃COOH) = 1.8 * 10^-5]

A) 0.11 M
B) 0.022 M
C) 0.072 M
D) 0.050 M
E) 0.015 M

Question 61

Calculate the minimum concentration of Cr³⁺ that must be added to 0.095 M NaF in order to initiate a precipitate of chromium(III) fluoride. (For CrF₃ , K_sp = 6.6 * 10^-11.)

A) 0.023 M
B) 0.032 M
C) 7.7 * 10^-8 M
D) 2.9 * 10^-9 M
E) 6.9 * 10^-10 M

Question 62

Will a precipitate of magnesium fluoride form when 200. mL of 1.9 * 10^-3 M MgCl₂ are added to 300. mL of 1.4 * 10^-2 M NaF? [K_sp (MgF₂) = 6.9 * 10^-9]

A) Yes, Q > K_sp
B) No, Q < K_sp
C) No, Q = K_sp
D) Yes, Q < K_sp
E) Yes, Q = K_sp

Question 63

The K_sp for silver(I) phosphate is 1.8 * 10^-18. Determine the silver ion concentration in a saturated solution of silver(I) phosphate.

A) 1.6 * 10^-5 M
B) 2.1 * 10^-5 M
C) 3.7 * 10^-5 M
D) 1.1 * 10^-13 M
E) 4.8 * 10^-5 M

Question 64

Calculate the silver ion concentration in a saturated solution of silver(I) sulfate (K_sp = 1.4 * 10^-5).

A) 1.5 * 10^-2 M
B) 2.4 * 10^-2 M
C) 3.0 * 10^-2 M
D) 1.4 * 10^-5 M
E) None of the above.

Question 65

Will a precipitate form (yes or no) when 50.0 mL of 1.2 * 10^-3 M Pb(NO₃)₂ are added to 50.0 mL of 2.0 * 10^-4 M Na₂S If so, identify the precipitate.

A) Yes, the precipitate is PbS
B) Yes, the precipitate is NaNO₃
C) Yes, the precipitate is Na₂S
D) Yes, the precipitate is Pb(NO₃)₂
E) No, a precipitate will not form

Question 66

Will a precipitate (ppt) form when 300. mL of 2.0 * 10^-5 M AgNO₃ are added to 200. mL of 2.5 * 10^-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

A) Yes, the ppt is AgNO₃(s)
B) Yes, the ppt is NaNO₃(s)
C) Yes, the ppt is NaI(s)
D) Yes, the ppt is AgI(s)
E) No, a precipitate will not form

Question 67

Calculate the concentration of fluoride ions in a saturated barium fluoride (K_sp = 1.7 * 10^-6) solution.

A) 7.6 * 10^-3 M
B) 1.5 * 10^-2 M
C) 3.4 * 10^-5 M
D) 1.7 * 10^-6 M
E) 3.4 * 10^-6 M

Question 68

Which of the following would decrease the K_sp for PbI₂

A) Lowering the pH of the solution
B) Adding a solution of Pb(NO₃)₂
C) Adding a solution of KI
D) None of the above-the K_sp of a compound is constant at constant temperature.

Question 69

The solubility product for calcium phosphate is K_sp = 1.3 * 10^-26. What is the molar solubility of calcium phosphate

A) 1.3 * 10^-26 M
B) 1.5 * 10^-7 M
C) 2.6 * 10^-6 M
D) 4.6 * 10^-6 M
E) 6.6 * 10^-6 M

Question 70

Calculate the minimum concentration of Mg²⁺ that must be added to 0.10 M NaF in order to initiate a precipitate of magnesium fluoride. (For MgF₂ , K_sp = 6.9 * 10^-9.)

A) 1.4 * 10⁷ M
B) 6.9 * 10^-9 M
C) 6.9 * 10^-8 M
D) 1.7 * 10^-7 M
E) 6.9 * 10^-7 M

Question 71

Calculate the molar solubility of BaCO₃ in a 0.10 M solution of Na₂CO₃(aq). (K_sp (BaCO₃) = 8.1 x 10^-9)

A) 8.1 x 10^-9 M
B) 9.0 x 10^-5 M
C) 8.1 x 10^-8 M
D) 2.8 x 10^-4 M
E) 0.10 M

Question 72

Calculate the concentration of chloride ions in a saturated lead(II) chloride (K_sp = 2.4 * 10^-4) solution.

A) 2.4 * 10^-4 M
B) 4.8 * 10^-4 M
C) 3.9 * 10^-2 M
D) 1.2 * 10^-1 M
E) 7.8 * 10^-2 M

Question 73

Will a precipitate of magnesium fluoride form when 300. mL of 1.1 * 10^-3 M MgCl₂ are added to 500. mL of 1.2 *10^-3 M NaF? [K_sp (MgF₂) = 6.9 *10^-9]

A) Yes, Q > K_sp
B) No, Q < K_sp
C) No, Q = K_sp
D) Yes, Q < K_sp
E) Yes, Q = K_sp

Question 74

Which response has both answers correct Will a precipitate form when 250 mL of 0.33 M Na₂CrO₄ are added to 250 mL of 0.12 M AgNO₃?
[K_sp(Ag₂CrO₄) = 1.1 * 10^-12] What is the concentration of the silver ion remaining in solution

A) Yes, [Ag⁺] = 2.9 * 10^-6 M
B) Yes, [Ag⁺] = 0.060 M
C) Yes, [Ag⁺] = 1.3 * 10^-4 M
D) No, [Ag⁺] = 0.060 M
E) No, [Ag⁺] = 0.105 M

Question 75

The K_sp value for lead(II) chloride is 2.4 * 10^-4. What is the molar solubility of lead(II) chloride

A) 2.4 * 10^-4 mol/L
B) 6.2 * 10^-2 mol/L
C) 7.7 * 10^-3 mol/L
D) 3.9 * 10^-2 mol/L
E) 6.0 * 10^-5 mol/L

Question 76

Will a precipitate (ppt) form when 20.0 mL of 1.1 * 10^-3 M Ba(NO₃)₂ are added to 80.0 mL of 8.4 * 10^-4 M Na₂CO₃

A) Yes, the ppt is Ba(NO₃ )₂
B) Yes, the ppt is NaNO₃
C) Yes, the ppt is BaCO₃
D) Yes, the ppt is Na₂CO₃
E) No, a precipitate will not form

Question 77

Calculate the silver ion concentration in a saturated solution of silver(I) carbonate (K_sp = 8.1 *10^-12).

A) 5.0 * 10^-5 M
B) 2.5 * 10^-4 M
C) 1.3 * 10^-4 M
D) 2.0 * 10^-4 M
E) 8.1 * 10^-4 M

Question 78

Calculate the molar solubility of CaF₂ in a 0.25 M solution of NaF(aq). (K_sp (CaF₂) = 4.0 x 10^-11)

A) 4.0 x 10^-11 M
B) 6.4 x 10^-10 M
C) 1.6 x 10^-10 M
D) 1.3 x 10^-5 M
E) 2.2 x 10^-4 M

Question 79

Will a precipitate (ppt) form when 300. mL of 5.0 * 10^-5 M AgNO₃ are added to 200. mL of 2.5 * 10^-7 M NaBr? Answer yes or no, and identify the precipitate if there is one.

A) Yes, the ppt is AgNO₃(s)
B) Yes, the ppt is AgBr(s)
C) Yes, the ppt is NaBr(s)
D) Yes, the ppt is NaNO₃(s)
E) No, a precipitate will not form

Question 80

To 1.00 L of a 0.100 M aqueous solution of benzoic acid (C₆H₅COOH) is added 1.00 mL of 12.0 M HCl. What is the percentage ionization of the benzoic acid in the resulting solution [K_a(C₆H₅COOH) = 6.5 * 10^-5]

A) 3.3%
B) 12%
C) 1.3%
D) 0.52%
E) 0.065%