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Coppin State University Department of Natural Sciences
CHEM 101.002 Exam #5 Dr. Alfred N. Amah
This examination consists of 40 multiple choice questions; carefully read each question and all the possible responses. Choose the correct answer by marking the alphabet before your choice on the scantron answer sheet. GOOD LUCK!
Multiple Choice Questions (100 points)
1. In a solution, the solvent:
a. is a liquid.
b. can be a liquid or gas
c. can be a solid, liquid or gas.
d. is never a solid.
e. is a substance present in the smallest concentration
2. A solution is prepared by dissolving 2 g of KCl in 100 g of H2O. In this solution, H2O is the,
e. ionic compound.
3. In water, a substance that ionizes completely in solution is called a:
a. weak electrolyte
e. strong electrolyte.
4. What is the molarity of a solution that contains 17 g of NH3 in 0.5 L of solution?
a. 34 M
b. 2.0 M
c. 0.50 M
d. 0.029 M
e. 1.0 M
5. What is the molarity of a solution containing 5.0 moles of KCl in 2.0 L of solution?
a. 2.5 M
b. 1.0 M
c. 5.0 M
d. 10.0 M
e. 2.0 M
6. What is the molarity of a solution which contains 58.5 g of sodium chloride dissolved in 0.500 L of solution?
a. 0.500 M
b. 1.00 M
c. 1.50 M
d. 2.00 M
e. 4.00 M
7. How many moles of CaCl2 are in 250 mL of a 3.0M of CaCl2 solution?
a. 750 moles
b. 1.3 moles
c. 83 moles
d. 0.75 mole
e. 3.0 moles
8. What volume of a 1.5 M KOH solution is needed to provide 3.0 moles of KOH?
a. 3.0 L
b. 0.50 L
c. 2.0 L
d. 4.5 L
e. 0.22 L
9. During the process of diluting a solution to a lower concentration,
a. the amount of solute does not change.
b. the amount of solvent does not change.
c. there is more solute in the concentrated solution.
d. The volume of the solution does not change.
e. Water is removed from the concentrated solution.
10. The hydrate of calcium chloride has the formula CaCl2.2H2O. What is the mass of 1.0 mole of this compound?
a. 129 g/mole
b. 147 g/mole
c. 111 g/mole
d. 199 g/mole
e. 2000 g/mole.
11. The hydrate of calcium chloride has the formula CaCl2.2H2O. What is the percent by mass of water in this compound?
12. The molarity of a solution of 5.0 g KCl in 100 mL of solution is ____.
a. 0.038 M
b. 0.067 M
c. 0.67 M
d. 0.13 M
e. 1.3 M
13. According to the Arrhenius concept , if HNO3 were dissolved in water, it would act as
a. a base.
b. an acid.
c. a source of hydroxide ions.
d. a source of H- ions.
e. a proton acceptor.
14. Which of the following is a characteristic of a base?
a. produces H3O+
b. has a sour taste.
c. has a slippery, soapy feel.
d. turns blue litmus red.
e. is insoluble in water.
15. What is the [OH-] in a solution that has [H3O+] = 1.0 x 10-6 M
a. 1 x 10-2 M
b. 1 x 10-6 M
c. 1 x 10-8 M
d. 1 x 10-10 M
e. 1 x 10-12 M
16. A solution with a pH of 4.0 is:
a. extremely acidic.
b. moderately acidic.
d. slightly basic.
e. Extremely basic.
17. What is the pH of a solution with [H3O+] = 1.0 x 10-9 M?
d. 1.0 x 10-5
18. What is the pH of a solution with [OH-] = 1.0 x 10-4 M?
e. 1.0 x 10-10
19. The [H3O+] of a solution with pH = 2.0 is?
a. 10.0 M
b. -10 M
c. 1.0 x 102 M
d. 1.0 x 10-2 M
e. 1.0 x 10-12 M
20. In which of the following are the pH values arranged from the most basic to the most acidic?
a. 1, 3, 6, 8, 11, 14
b. 2, 5, 7, 9, 10, 11
c. 14, 10, 7, 4, 3, 1
d. 14, 10, 7, 1, 3, 5
e. 7, 10, 14, 4, 3, 1
21. In a neutralization reaction:
a. two acids react to from water.
b. water and salt react to form an acid and a base.
c. an acid and a salt react to form water and a base.
d. A base and a salt react to form water and an acid.
e. An acid and a base react to form salt and water.
22. The neutralization reaction between Al(OH)3 and HNO3 produces the salt with the formula:
23. How many moles of H2O are produced when 1.0 mole of Mg(OH)2 reacts with 1.0 mole of H2SO4?
a. 1.0 mole
b. 2.0 moles
c. 3.0 moles
d. 4.0 moles
e. 5.0 moles
24. Which of the following is a neutralization reaction?
a. KCl + NaNO3 → KNO3 + NaCl
b. KOH + HNO3 → H2O + KNO3
c. SO3 + H2O → H2SO4
d. 4Na + O2 → 2N2O
e. 2NO2 → 2NO + O2
25. What is the molarity of a KCl solution made by diluting 75.0 mL of 0.200 M solution to a final volume of 100.0 mL?
a. 0.267 M
b. 0.150 M
c. 0.200 M
d. 6.670 M
e. 0.100 M
26. What volume of 0.10 M NaOH can be prepared from 250.0 mL of 0.3 M NaOH?
a. 0.075 L
b. 0.25 L
c. 0.75 L
d. 0.083 L
e. 750 L
27. In a sulfuric acid solution the [H2SO4] is 0.005 M. What is the pH?
a. pH = 12
b. pH = 2
c. pH = 3
d. pH = 11
e. pH = 5
28. When a piece of magnesium metal (Mg) is added to hydrochloric acid, what gas is produced?
d. carbon dioxide
For the next two questions, consider the reaction in which magnesium reactc with an HCl solution.
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2 (g)
29. If 2.00 g of Mg reacts completely with 50.0 mL of HCl solution, what is the molarity of the HCl solution?
a. 1.65 M
b. 80.0 M
c. 8.00 M
d. 0.823 M
e. 3.29 M
30. If 2.00 g of Mg reacts with excess HCl solution, how many liters of hydrogen gas are produced at STP? (Hint: 1.0 mole of a gas = 22.4 liters @ STP).
a. 3.69 L
b. 1.84 L
c. 5.53 L
d. 22.4 L
e. 0.165 L
31. Metal oxides react with water to produce ________.
a. hydrogen gas
e. reduced metals
32. How many liters of 0.1107 M NaOH contain 10.00 g of NaOH?
a. 0.7290 L
b. 1.107 L
c. 2.258 L
d. 3.198 L
e. 4.428 L
33. If 1.928 g KNO3 is dissolved in enough water to make 250.0 mL of solution, what is the molarity of potassium nitrate?
a. 6.912 x 10-4 M
b. 4.767 x 10-3 M
c. 7.627 x 10-2 M
d. 1.297 x 10-1 M
e. 7.712 M
34. What is the mass in grams, of solute in 0.175 L of 3.17 x 10-2 M KCl?
a. 0.00555 g
b. 0.181 g
c. 0.255 g
d. 0.414 g
e. 13.5 g
35. Which of the following directions correctly describes the preparation of 0.500 L of 0.150 M NaOH from 6.00 M stock solution?
a. Dilute 0.200 L of 6.00 M NaOH to a volume of 0.500 L.
b. Dilute 12.5 mL of 6.00 M NaOH to a volume of 0.500 L.
c. Combine 0.200 L of 6.00 M NaOH with 0.500 L of water.
d. Dilute 475 mL of 6.00 M NaOH to a volume of 0.500 L.
e. Combine 12.5 mL of 6.00 M NaOH with 0.500 L of water.
36. A 25.00 mL sample of NaOH is titrated with 15.23 mL of 0.2250 M HCl. What is the concentration of the NaOH solution?
a. 2.198 x 10-3 M
b. 0.02872 M
c. 0.1371 M
d. 0.3693 M
e. 0.5223 M
37. Which of the following is a weak base?
38. Sulfuric acid is the product of the reaction of ______ and H2O.
39. Choose the best classification of the reaction represented by the following
equation: 2Fe3+ (aq) + Fe(s) → 3Fe2+ (aq)
40. Choose the best classification of the reaction represented by the following equation:
HNO3 (aq) + KOH(aq) → KNO3(aq) + H2O (l)
The end! (Chemistry is fun and Chem-is-try )
How do you calculate normality from molarity? Steps Gather information about the equivalent weight of the reacting substance. Consult chemical reference books to find out the valence and the molecular weight of the substance. Figure the equivalent weight of the substance. The equivalent weight of the substance is equal to the molecular weight divided by the valence. Calculate normality. ... Try an example. ...