# unit 2 practice test ```Name _________________________
Period _____
Unit 2 Practice Test
Use the following to answer questions 1 and 2. A student places a 2.4 g
sample of magnesium ribbon into 500 mL of 2.0 M hydrochloric acid solution.
The student records that bubbling occurs and that the ribbon disappears.
1. What is the balanced equation for this reaction?
a. Mg + HCl  MgCl + H
b. Mg + 2HCl MgH2 + Cl2
c. Mg + 2HCl  MgCl2 + H2
d. Mg + 2HCl  Mg + Cl2 + H2
2. Identify which substance is being oxidized and which substance is being
reduced in this laboratory investigation.
a. Magnesium is being oxidized &amp; the chloride ion is being reduced
b. Magnesium is being reduced &amp; the chloride ion is being oxidized
c. Magnesium is being oxidized &amp; the hydrogen ion is being reduced
d. Magnesium is being reduced &amp; the chloride ion is being oxidized
3. If 200 mL of 0.60 M MgCl2is added to 400 mL of distilled water, what is
the concentration of Mg2+ (aq) and Cl- (aq) in the resulting solution?
a. 0.20 M Mg2+ and 0.20 M Clb. 0.20 M Mg2+ and 0.40 M Clc. 0.40 M Mg2+ and 0.40 M Cld. 2.0 M Mg2+ and 2.5 M Cl4. Determine the amount of distilled water that should be added to 20.0 mL
of 12.0 M HCl (aq) in order to prepare a 0.500 M HCl (aq) solution.
a. 120 mL
b. 140 mL
c. 460 mL
d. 480 mL
5. What is the molarity of a solution containing ClO2- (aq) if 15.0 mL of the
solution is needed to react completely with 20.0 mL of 0.20 M KMnO4
solution?
2H2O (l) + 4 MnO4- (aq) + 3ClO2- (aq)  4 MnO2 (s) + 3 ClO4- (aq) + 4OH- (aq)
a.
b.
c.
d.
0.10
0.20
0.30
0.40
M
M
M
M
Use the following information for the next 2 questions. Solutions of lead (II)
nitrate and potassium iodide react according to the following reaction:
Pb(NO3)2 (aq) + 2KI (aq)  PbI2 (s) + 2KNO3 (aq)
Suppose that the lead nitrate is reacted with excess potassium iodide.
6. Which species act exclusively as spectator ions?
a. K+ and NO3b. Pb2+ and Ic. K+ and Pb2+
d. I- and NO37. What would be the composition of the solution after the reaction occurs?
a. Solid lead (II) iodide and equal numbers of potassium ions and
nitrate ions
b. Solid lead (II) iodide and more potassium ions than nitrate ions
c. Solid lead (II) iodide and potassium, nitrate and iodide ions in
unequal amounts
d. Solid lead (II) iodide and equal numbers of potassium, nitrate and
iodide ions.
8. A sample of 25.0 mL of 0.120 M Ca(OH)2 (aq) is titrated with 0.150 M HCl
(aq). What volume of HCl (aq) is needed to completely neutralize the
Ca(OH)2 (aq)?
a. 20.0 mL
b. 40.0 mL
c. 60.0 mL
d. 80.0 mL
9. In which of the following species is the oxidation state for nitrogen the
greatest?
a. NO
b. NO2
c. N2O
d. N2O5
10.
A 1.0 M solution of table salt (NaCl) is considered to be 1.0 M Na+
and 1.0 M Cl-. This means table salt is a:
a. Strong electrolyte
b. Weak electrolyte
c. Nonelectrolyte
d. Strong acid
11.
What volume of 0.2000 M sulfuric acid is required to neutralize
800.0 mL of 0.1000 M potassium hydroxide?
a. 200.0 mL
b. 400.0 mL
c. 800.0 mL
d. 1600.0 mL
12.
Consider 100.0 mL of a 1.00 M solution of NaCl in a beaker. After
several days, you test the solution and find that it has a concentration of
1.33 M. How much water must have evaporated?
a. 20.0 mL
b. 25.0 mL
c. 75.0 mL
d. 80.0 mL
13.
What volume of 10.0 M NaOH must be used to prepare 500 mL of a
2.50 M solution?
a. 125 mL
b. 200 mL
c. 250 mL
d. 12.5 mL
14.
Hydrogen reacts with oxygen to form water. If 16 grams of
hydrogen is mixed with 16 grams of oxygen, how much water can form?
a. 0.50 grams
b. 8.0 grams
c. 18 grams
d. 72 grams
15.
Consider the neutralization reaction Be(OH)2 (s) + 2HCl (aq)  BeCl2
(aq) + 2H2O (l). What volume of 5.00 M HCl is required to react
completely with 4.30 g of Be(OH)2? (Molar mass of Be(OH)2 = 43.0 g/mol)
a. 10.0 mL
b. 30.0 mL
c. 40.0 mL
d. 50.0 mL
16.
Solutions of CaCl2 and Na2CO3 are mixed and a precipitate is
formed. What is the net ionic equation for the reaction?
a. CO32- (aq) + Ca2+(aq)  CaCO3 (s)
b. 2Cl- (aq) + 2Na+ (aq)  2NaCl (s)
c. CO32- (aq) + Ca2+(aq) + 2Cl- (aq) + 2Na+ (aq)  CaCO3 (s) + 2NaCl (aq)
d. CO32- (aq) + Ca2+(aq)  Ca(CO3)2 (s)
17.
Which of the following pairs of ions would not form a solid in
aqueous solution?
a. Ba2+ and SO4b. Pb2+ and Brc. Na+ and SO4d. Pb2+ and S218.
a.
b.
c.
d.
The oxidation number of N in Ca(NO3)2 is:
+2
+3
+4
+5
Free Response:
19.
Two solutions are prepared, one of Cu(NO3)2 and one of KOH.
a. Draw molecular representations of the two solutions, assuming that
one beaker contains four formula units of Cu(NO3)2 and the other
beaker contains six formula units of KOH.
Cu(NO3)2
KOH
b. Draw a molecular representation of the solution that results when
the contents of the beakers are mixed. Include the correct number
of formula units or ions, and the correct amounts and kinds of ions
remaining.
Resulting
Solution
c. Write the balanced net ionic equation for the reaction.
20.
Nonprescription antacids may contain MgO, Mg(OH)2, or Al(OH)3.
a. Write a balanced neutralization reaction for the neutralization of
hydrochloric acid by each of these substances.
b. Which of these substances will neutralize the greatest amount of
0.1 M HCl per gram?
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