Chapters 4 and 5 Practice Test
1. Which of these compounds is a weak electrolyte?
A. HCl
B. CH3COOH (acetic acid)
C. C6H12O6 (glucose)
D. O2
E. NaCl
2. The balanced net ionic equation between aqueous diethyl ammonium chloride and aqueous potassium hydroxide contains which of the following species? A. KCl(s) B. 2 OH-1 C. (CH3CH2)2NH2 (aq) D. H3O+1 E. (CH3CH2)2NH2+1 (aq)
3. In the chemical reaction 5H2O2 + 2MnO4- + 6H+ ( 2Mn2+ + 8H2O + 5O2, the oxidizing agent is A. H2O2.
B. MnO4-1.
C. H+.
D. Mn2+.
E. O2.
4. It takes 32.0 seconds for ammonia gas to effuse down a capillary tube. How long will it take for hydrogen chloride …show more content…
gas to effuse down an identical tube under identical conditions of temperature and pressure? A. 22 seconds B. 54 seconds C. 47 seconds D. 61 seconds E. 32 seconds
5. 50.0 mL of 0.250 M nitric acid is added to 50.0 mL of 0.400 M magnesium nitrate. What is the concentration of nitrate ion in the final solution?
A. 0.525 M
B. 0.263 M
C. 0.325 M
D. 1.05 M
E. 0.0295 M
6. At what temperature will a gaseous xenon tetrafluoride molecule have the same average speed as a fluorine molecule at 15°C? A. 200. °C B. 950. °C C. 15 °C D. 600. °C E. 1300. °C
7. 2.00 grams of calcium metal is dissolved in water. What is the final concentration of hydroxide ions if 750. mL of water are used?
A. 0.133 M
B. 0.0667 M
C. 0.266 M
D. 0.792 M
E. 0.0500 M
8. A balloon contains an anesthetic mixture of cyclopropane (cp) and oxygen (O2) at 200. torr and 800. torr, respectively. What is the ratio of the number of moles of cyclopropane to moles of oxygen?
ncp/no2 = ?
A. 0.20 B. 0.25 C. 0.33 D. 0.50 E. 0.75
9. Oxygen gas, generated by the reaction 2KClO3(s) → 2KCl(s) + 3O2(g), is collected over water at 27(C in a 2.00-L vessel at a total pressure of 650. torr. (The vapor pressure of H2O at 27(C is 26.0 torr.) How many moles of KClO3 were consumed in the reaction?
A. 0.0790 moles B. 0.119 moles C. 0.0527 moles D. 0.0813 moles E. 0.0440 moles
10. The balanced net ionic equation for the reaction between aqueous ammonia and aqueous nickel (II)
nitrate contains which of the following?
A. [Ni(NH3)4]+2 (aq)
B. 2 OH-1
C. 2 Ni+2
D. Ni(OH)2(aq)
E. 2 NH3
11. The balanced net ionic equation for the reaction between aqueous ammonia and aqueous carbonic
acid contains which of the following?
A. NH4+1 (aq)
B. CO3-2 (aq)
C. H2O
D. H3O+1(aq)
E. Both B and C
12. What volume of H2O(g) measured at STP is produced by the combustion of 4.00 g of methane gas (CH4)?
A. 5.60 L B. 11.2 L C. 22.4 L D. 33.6 L E. 44.8 L
13. A 3.31-g sample of lead nitrate is heated in an evacuated cylinder with a volume of 1.62 L. The salt decomposes when heated, according to the equation
2Pb(NO3)2(s) → 2PbO(s) + 4NO2(g) + O2 (g)
Assuming complete decomposition, what is the pressure in the cylinder after decomposition and cooling to a temperature of 300 K? Assume the PbO(s) takes up negligible volume.
A. 0.380 atm B. 0.228 atm C. 0.0342 atm D. 1.38 atm E. 0.780 atm
14. A 4.32 gram sample of a certain diatomic gas occupies a volume of 3.00-L at 1.00 atm and a temperature of 57(C. Identify this gas.
A. F2 B. N2 C. H2 D. O2 E. Cl2
15. The balanced net ionic equation for the reaction between aqueous hydrosulfuric acid and aqueous
calcium hydroxide contains which of the following?
A. Ca(OH)2(s)
B. H+1 (aq)
C. CaS(aq)
D. 2 H2O
E. Both C and D
16. 300.0 mL of 1.20 M lead (II) nitrate is mixed with 200.0 mL of 2.00 M potassium iodide. Select the
true item about the resulting mixture.
A. The final concentration of the iodide ion is 0.800 M
B. The final concentration of the nitrate ion is 2.40 M
C. The final concentration of the lead (II) ion is 0.530 M
D. The final concentration of the potassium ion is 4.00 M
E. The final concentration of the lead (II) ion is 0.320 M
17. . Concentrated ammonia solution is added to a precipitate of silver carbonate. The balanced net ionic
equation contains which of the following?
A. NH3
B. Ag2CO3(aq)
C. CO3-2
D. [Ag(NH3)]+1
E. Ag+1
18. In the reaction P4(s) + 10Cl2(g) → 4PCl5(s), the reducing agent is
A. chlorine. B. PCl5. C. phosphorus. D. Cl–. E. none of these
19. For the reaction of sodium bromide with chlorine gas to form sodium chloride and bromine, the appropriate half-reactions are (ox = oxidation and re = reduction):
A. ox: Cl2 + 2e– → 2Cl–; re: 2Br– → Br2 + 2e– B. ox: 2Br– → Br2 + 2e–; re: Cl2 + 2e– → 2Cl– C. ox: Cl + e– → Cl–; re: Br → Br– + e– D. ox: Br + 2e– → Br2–; re: 2Cl– → Cl2 + 2e– E. ox: 2Na+ + 2e– → 2Na; re: 2Cl– → Cl2 + 2e–
20. Given the following redox reaction in acidic media:
H2O2 + Cr2O72– →
answer the following question: The coefficient for H+1 in the balanced reaction is
A. 2. B. 4. C. 6. D. 8. E. 14.
21. Which conditions of P, T, and n, respectively, are most ideal?
A. high P, high T, high n B. low P, low T, low n C. high P, low T, high n D. low P, high T, high n E. low P, high T, low n
22. You have 28.0 g of O2 gas in a container with twice the volume as one with SO3 gas. The pressure and temperature of both containers are the same. Calculate the mass of sulfur trioxide gas you have in the container.
A. 35.0 g B. 28.0 g C. 21.0 g D. 12.0 g E. 40.0 g
23. You are holding two balloons, an orange balloon and a blue balloon. The orange balloon is filled with neon (Ne) gas and the blue balloon is filled with argon (Ar) gas. The orange balloon has twice the volume of the blue balloon. Which of the following best represents the mass ratio of Ne:Ar in the balloons?
A 1 : 1 B.
1 : 2 C. 2 : 1 D. 1 : 3 E. 3 : 1
24. A solution contains the ions Ag+, Pb2+, and Ni2+. Dilute solutions of NaCl, Na2SO4, and Na2S are available to separate the positive ions from each other. In order to effect separation, the solutions should be added in which order?
A. Na2SO4, NaCl, Na2S B. Na2SO4, Na2S, NaCl C. Na2S, NaCl, Na2SO4 D. NaCl, Na2S, Na2SO4 E. NaCl, Na2SO4, Na2S
25. The following unbalanced equation represents a reaction that occurs in basic solution:
MnO41– + C2O42– → MnO2 + CO32–
How many moles of MnO41– are required to produce 1 mole of CO32–?
A. 4 B. 3 C. 2 D. 0.67 E. 0.33
26. Given reaction 2NH3(g) + 3Cl2(g) → N2(g) + 6HCl(g), you react 5.0 L of NH3 with 5.0 L of Cl2 measured at the same conditions in a closed container. Calculate the ratio of pressures in the container (Pfinal/Pinitial).
A. 0.75 B. 1.00 C. 1.33 D. 1.50 E. …show more content…
2.00
27.
The valve between a 5-L tank containing a gas at 9 atm and a 10-L tank containing a gas at 6 atm is opened. Calculate the final pressure in the tanks.
A. 3 atm B. 4 atm C. 7 atm D. 15 atm E. 12 atm
28. A sample of helium gas occupies 12.4 L at 27(C and 1.00 atm. What volume will it occupy at 87(C and 1.20 atm?
A. 0.750 L B. 6.28 L C. 12.4 L D. 10.4 L E. 17.2 L
29. The root mean square velocity of HCl molecules at a given temperature is 1200 miles/hour. What is the velocity in miles/hour of He atoms at the same temperature? A. 900. mph B. 10,800 mph C. 100. mph D. 400. mph E. 3600 mph
30. Acidified permanganate solution is added to a solution of hydrogen peroxide.
Determine the number of electrons involved in this reaction.
A. 10 B. 8 C. 6 D. 4 E.
2
31. What mass of sodium hydroxide is required to react exactly with 25.0 mL of 1.2 M sulfuric acid?
A. 1.2 g B. 1.8 g C. 2.4 g D. 3.6 g E. 0.60 g
32 through 34: Consider three 1-L flasks at STP. Flask A contains NH3 gas, flask B contains NO2 gas, and flask C contains N2 gas.
32. Which contains the largest number of molecules?
A. flask A B. flask B C. flask C D. all are the same E. none
33. In which flask are the molecules least polar and therefore most ideal in behavior?
A. flask A B. flask B C. flask C D. all are the same E. none
34. In which flask do the molecules have the highest average velocity?
A. flask A B. flask B C. flask C D. all are the same E. none
35. If 6.00 grams of solid calcium carbonate is added to 40.0 mL of 2.50 M hydrochloric acid determine the volume of gas produced under room conditions of 27.0 ˚C and 1.00 atm. pressure. A. 1.50 L B. 1.85 L C. 1.23 L D. 0.82 L E. 0.62 L
36. An unknown acid sample is titrated with 0.400 M potassium hydroxide. 2.0 grams of the acid sample are weighed out and dissolved in 50.0 mL of water. It is found that 40.0 mL of the base are required to neutralize the acid. Assuming the acid is diprotic determine the molar mass of the acid. A. 100. g/mole B. 125 g/mole C. 175 g/mole D. 250. g/mole E. 330. g/mole
37. Powdered magnesium oxide is added to a container of carbon dioxide gas. Select the correct product(s) for this reaction. A. Mg(OH)2 B. MgCO3 C. H2O D. Mg(HCO3)2 E. both A and C
38. A balloon has a volume of 1.20 liters at 27.0(C. The balloon is heated to 54.0(C. Calculate the new volume of the balloon.
A. 1.20 L B. 1.30 L C. 1.70 L D. 2.10 L E. 2.40 L
39. Determine the molecular formula of a gas with empirical formula S2O if it has a density of 10.0 g/L at a temperature of 27°C at a pressure of 1.00 atm. (Use a value of 0.0800 for R) A. S4O2 B. S6O3 C. S4O2 D. S2O E. S6O3
40. 60.0 mL of 0.400 M potassium carbonate solution is mixed with 80.0 mL of 0.250 M silver sulfate solution. Determine the mass of product formed. A. 2.75 g B. 6.62 g C. 5.50 g D. 11.0 g E. 4.20 g
Free Response
1. A mixture of H2(g), O2(g), and 2 milliliters of H2O (l) Is present in a 0.500 liter rigid container at 25 ˚C. The number of moles of H2 and the number of moles of O2 are equal. The total pressure is 1,146 millimeters of mercury. The equilibrium vapor pressure of pure water at 25˚C is 24 mm Hg. The mixture is sparked, and H2 and O2 react until one reactant is completely consumed.
(a) Identify the reactant remaining and calculate the number of moles of the reactant remaining.
(b) Calculate the total pressure in the container at the conclusion of the reaction if the final temperature is 90 ˚C. The equilibrium vapor pressure of water at 90 ˚C Is 526 mmHg.
(c) Calculate the number of moles of water present as vapor in the container at 90 ˚C.
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Answers
1. B 21. E
2. E 22. A
3. B 23. A
4. C 24. A
5. A 25. E
6. E 26. C
7. A 27. C
8. B 28. C
9. E 29. E
10. B 30. A
11. A 31. C
12. B 32. D
13. A 33. C
14. A 34. A
15. D 35. C
16. E 36. D
17. C 37. B
18. C 38. B
19. B 39. E
20. D 40. C
Free Response
(a) O2 remains, 0.00755 moles
(b) Ptotal = 868 mmHg
(c) nwater vapor = 0.0116 moles