AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
Name _______________________________________
Date ______________
SECTION I: Multiple Choice
NO CALCULATOR MAY BE USED.
Note: For all questions, assume that the temperature is 298 K, the pressure is 1.00 atmosphere, and solutions are
aqueous unless otherwise specified.
Directions: Each of the questions or incomplete statements below is followed by five suggested answers or
completions. Select the one that is best in each case and then circle the letter.
1. 100 mL of a 1.0 M HCl solution and 100 mL of a
5.0 M NaCl solution are mixed. What is the final
molarity of the chloride (Cl−) ion?
(A) 3 M
(B) 4 M
(C) 5 M
(D) 6 M
2. What mass of FeSO4 ⋅ 6 H2O, molar mass = 260. g mol−1, is
required to produce 500. mL of a 0.100 M iron(II) sulfate
solution?
(A)
9.00 g
(B)
13.0 g
(C)
36.0 g
(D)
72.0 g
3. 100.0 mL of a 4.00 M KBr solution, molar mass = 119.0 g mol−1,
would contain how many grams of KBr?
(A)
(B)
2.38 g
47.6 g
(C) 119 g
(D) 500. g
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
4. When sodium chloride is added to a saturated aqueous
solution of silver chloride, which of the following
precipitates would be expected to appear?
(A) sodium
(B) silver
(C) sodium chloride
(D) silver chloride
5. A substance is dissolved in water, forming a 0.50 M
solution. If 4.0 L of solution contains 240 g of the
substance, what is the molar mass of the substance?
(A)
60. g mol−1
(B) 120 g mol−1
(C) 240 g mol−1
(D) 480 g mol−1
6. A 0.1 M solution of which of the following acids will be
the best conductor of electricity?
(A) HNO3
(B) H2CO3
(C) H2S
(D) HF
7. If 46 g of MgBr2, molar mass = 184 g mol−1, is dissolved in
water to form 0.50 L of solution, what is the concentration
of bromide ions in the solution?
(A) 0.50 M
(B) 1.0 M
(C) 2.0 M
(D) 4.0 M
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
8. How many moles of Na2SO4 must be added to 500 mL of
water to create a solution that has [Na+] = 2 M ? (Assume
the volume of the solution does not change.)
(A) 0.5 mol
(B) 1 mol
(C) 2 mol
(D) 4 mol
9. How many liters of water must be added to 4 L of a 6 M
HNO3 solution to create a solution that is 2 M ?
(A)
2L
(B)
4L
(C)
8L
(D) 12 L
10. A beaker contains 50.0 mL of a 0.20 M Na2SO4 solution. If
50.0 mL of a 0.10 M solution of Ba(NO3)2 is added to the
beaker, what will be the final concentration of sulfate ions
in the solution?
(A) 0.20 M
(B) 0.10 M
(C) 0.050 M
(D) 0.025 M
11. When 300. mL of a 0.60 M NaCl solution is combined with
200. mL of a 0.40 M MgCl2 solution, what will be the
molar concentration of Cl− ions in the solution?
(A) 0.17 M
(B) 0.34 M
(C) 0.51 M
(D) 0.68 M
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
12. A student added 0.10 mol of NaBr and 0.20 mol of BaBr2
to 2 L of water to create an aqueous solution. What is the
minimum number of moles of AgC2H3O2 that the student
must add to the solution to precipitate out all of the Br−
ions as AgBr?
(A) 0.20 mol
(B) 0.40 mol
(C) 0.50 mol
(D) 1.00 mol
13. A student added 1 L of a 1.0 M KCl solution to 1 L of a 1.0 M
Pb(NO3)2 solution. A lead(II) chloride precipitate formed, and
nearly all of the lead ions disappeared from the solution. Which of
the following lists the ions remaining in the solution in order of
decreasing concentration?
(A) [NO3−] > [K+] > [Pb2+]
(B) [NO3−] > [Pb2+] > [K+]
(C) [K+] > [Pb2+] > [NO3−]
(D) [K+] > [NO3−] > [Pb2+]
14. What is the final [K+] in a solution made by mixing
300. mL of 1.0 M KNO3 and 700. mL of 2.0 M
K3PO4?
(A) 1.5 M
(B) 2.0 M
(C) 3.0 M
(D) 4.5 M
15. Strontium sulfate will precipitate when a solution of sodium
sulfate is added to a strontium nitrate solution. What will be
[Sr2+] remaining after 30.0 mL of a 0.10 M Na2SO4 solution are
added to 70.0 mL of 0.20 M Sr(NO3)2 solution?
(A) 0.15 M
(B) 0.11 M
(C) 0.20 M
(D) 0.030 M
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
16. Which of the following is a strong electrolyte when
it is mixed with water?
(A) HNO2
(B) KNO3
(C) C2H5OH
(D) NH3
2 HBr(aq) + Zn(s) → ZnBr2(aq) + H2(g)
17. A 13.1-g piece of solid Zn was placed in a container. A
0.10 M solution of HBr was slowly added to the container
until the Zn was completely dissolved, according to the
balanced equation shown above. What was the volume of
HBr solution required to completely dissolve the solid Zn?
(A) 1.0 L
(B) 2.0 L
(C) 4.0 L
(D) 5.0 L
18. A chemist needs 400.0 mL of a 0.60 M nitrate ion, NO3−,
solution. He has 400.0 mL of a 0.20 M Mg(NO3)2 solution.
How many moles of solid NaNO3 will he need to add to
increase the concentration to the desired value?
(A) 0.04 mol
(B) 0.08 mol
(C) 0.16 mol
(D) 0.20 mol
19. 3 Cu(s) + 8 HNO3(aq) → 3 Cu(NO3)2(aq) + 2 NO(g) + 4 H2O(ℓ)
Copper metal reacts with nitric acid according to the above
equation. A 0.30-mol sample of copper metal and 10.0 mL of
12.0 M nitric acid are mixed in a flask. How many moles of
NO gas will form?
(A) 0.120 mol
(B) 0.060 mol
(C) 0.030 mol
(D) 0.010 mol
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
20. 2 CrO42−(aq) + 3 SnO22−(aq) + H2O(ℓ) → 2 CrO2−(aq) + 3 SnO32−(aq) + 2 OH−(aq)
How many moles of OH− form when 50.0 mL of 0.100 M CrO42− is
added to a flask containing 50.0 mL of 0.100 M SnO22− ?
(A) 3.33 × 10−3 mol
(B) 4.00 × 10−3 mol
(C) 5.00 × 10−3 mol
(D) 7.50 × 10−3 mol
SECTION II: Free Response
YOU MAY USE YOUR CALCULATOR.
CLEARLY SHOW THE METHOD USED AND THE STEPS INVOLVED IN ARRIVING AT YOUR
ANSWERS. It is to your advantage to do this, since you may obtain partial credit if you do and you will receive
little or no credit if you do not. Attention should be paid to significant figures.
1. Calculate the mass of precipitate formed when 2.27 L of 0.0820 M Ba(OH)2 are mixed with 3.06 L
of 0.0664 M Na2SO4.
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
2. You have two 500.00-mL aqueous solutions. Solution A is a solution of silver nitrate, and solution B is a
solution of potassium chromate. The masses of the solutes in each of the solutions are the same. When the
solutions are added together, a blood-red precipitate forms. After the reaction has gone to completion, you
dry the solid and find that it has a mass of 331.8 g.
(a) Write a balanced chemical equation for the reaction that occurs. Be sure to include states.
(b) Calculate the mass of silver nitrate, in grams, that was initially present in Solution A.
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
(c) Calculate the molar concentration of the potassium ions in the original potassium chromate solution.
(d) Calculate the molar concentration of the chromate ions in the final solution.
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AP Chemistry
Mr. Trubic
St. John’s College High School
Chapter 4: AP Problem Set
Na2S(aq) + CuSO4(aq) → Na2SO4(aq) + CuS(s)
3. The concentration of Cu2+ ions in the water (which also contains sulfate ions) discharged from a certain
industrial plant is determined by adding excess sodium sulfide (Na2S) solution to 0.800 L of the water. The
molecular equation is shown above.
(a) Write the net ionic equation.
(b) Calculate the molar concentration of Cu2+ in the water sample if 0.0177 g of solid CuS is formed.
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