48) How many milliliters of 0.260 M Na2S are needed to react with 45.00 mL of 0.315 M AgNO3?
Na2S(aq) + 2 AgNO3(aq) → 2 NaNO3(aq) + Ag2S(s)
A) 27.3 mL
B) 54.5 mL
C) 74.3 mL
D) 109 mL
49) How many grams of CaCl2 are formed when 25.00 mL of 0.00237 M Ca(OH)2 reacts with excess Cl2
gas?
2 Ca(OH)2(aq) + 2 Cl2(g) → Ca(OCl)2(aq) + CaCl2(s) + 2 H2O(l)
A) 0.00329 g
B) 0.00658 g
C) 0.0132 g
D) 0.0304 g
50) When 125 mL of 0.500 M AgNO3 is added to 100. mL of 0.300 M NH4Cl, how many grams of AgCl
are formed?
AgNO3(aq) + NH4Cl(aq) → AgCl(s) + NH4NO3(aq)
A) 4.30 g
B) 8.96 g
C) 13.3 g
D) 25.8 g
51) How many milliliters of 0.200 M FeCl3 are needed to react with an excess of Na2S to produce 0.345 g
of Fe2S3 if the percent yield for the reaction is 65.0%?
3 Na2S(aq) + 2 FeCl3(aq) → Fe2S3(s) + 6 NaCl(aq)
A) 6.38 mL
B) 10.8 mL
C) 12.8 mL
D) 25.5 mL
52) If 100. mL of 0.200 M Na2SO4 is added to 200. mL of 0.300 M NaCl, what is the concentration of Na+
ions in the final solution? Assume that the volumes are additive.
A) 0.267 M
B) 0.333 M
C) 0.500 M
D) 0.700 M
53) The unknown acid H2X can be neutralized completely by NaOH according to the following equation:
H2X(aq) + NaOH(aq) → Na2X + H2O
To completely neutralize this reaction, 250 mL of 0.13 M NaOH were needed. How many moles of H2X
were present?
A) 0.033
B) 0.065
C) 0.016
D) 3.8
54) What is the oxidation number of the sulfur atom in Li2SO4?
A) -2
B) +2
C) +4
D) +6
55) What is the oxidation number of the sulfur atom in Cs2SO3?
A) -2
B) +2
C) +4
D) +6
56) What is the oxidation number of the chromium atom in Li2Cr2O4?
A) -2
B) +2
C) +6
D) +7
57) What is the oxidation number of the oxygen atom in O22-?
A) -2
B) -1
C) +1
D) +2
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58) What is the oxidation number change for the chromium atom in the following unbalanced reduction
half reaction?
Cr2O72-(aq) + H+(aq) → Cr3+(aq) + H2O(l)
A) -7
B) -3
C) +3
D) +6
59) In which compound is the oxidation state of oxygen not –2?
A) MgO
B) Na2O
C) K2O2
D) Al2O3
60) In which compound is the oxidation state of hydrogen not +1?
A) H2S
B) H2O2
C) KH
D) KHSO4
61) Which species functions as the oxidizing agent in the following reduction-oxidation reaction?
Zn(s) + Ni2+(aq) → Ni(s) + Zn2+(aq)
A) Ni(s)
B) Ni2+(aq)
C) Zn(s)
D) Zn2+(aq)
62) Using the following portion of the activity series for oxidation half reactions, determine which
combination of reactants will result in a reaction.
Ca(s) → Ca2+(aq) + 2 e–
Ag(s) → Ag +(aq) + e–
A) Ca(s) with Ag(s)
B) Ca(s) with Ag +(aq)
C) Ca2+(aq) with Ag +(aq)
D) Ca2+(aq) with Ag(s)
63) Using the following portion of the activity series for oxidation half reactions
Mg(s) → Mg2+(aq) + 2e–
Co(s) → Co2+(aq) + 2e–
Cu(s) → Cu2+(aq) + 2e–
indicate which pairs of reactions will occur.
A) Cu(s) with Co2+(aq) and Co(s) with Mg2+(aq)
B) Mg(s) with Cu2+(aq) and Co2+(aq) with Mg2+(aq)
C) Mg(s) with Cu(s) and Co(s) with Cu(s)
D) Mg(s) with Co2+(aq) and Co(s) with Cu2+(aq)
64) Using the following portion of the activity series for oxidation half reactions
Li(s) → Li+(aq) + e–
Al(s) → Al3+(aq) + 3e–
Fe(s) → Fe2+(aq) + 2e–
Pt(s) → Pt2+(aq) + 2e–
determine which pairs of reactions will occur.
A) Al(s) with Fe2+(aq) and Pt(s) with Li+(aq)
B) Fe(s) with Al(s) and Al3+(aq) with Pt2+(aq)
C) Fe(s) with Pt2+(aq) and Al(s) with Pt2+(aq)
D) Li(s) with Al3+(aq) and Fe(s) with Al3+(aq)
65) Coinage metals are metals that are not easily oxidized. Based on the activity series, which metal
would be least desirable as a coinage metal?
A) Mn
B) Au
C) Ca
D) Co
66) Based on the activity series, which metal dissolves in hydrochloric acid to produce hydrogen gas, but
does not react with steam or liquid water?
A) Mg
B) Hg
C) Sn
D) K
67) Which element will react rapidly with aqueous H+ ions and also with liquid H2O?
A) Pt
B) Co
C) Zn
D) Ca
68) Which elementwill not react with liquid water but will react with aqueous H+ ions and steam?
A) K
B) Fe
C) Sn
D) Hg
69) Which element will not react with liquid water or with aqueous H+ ions?
A) Hg
B) Co
C) Zn
D) Li
70) How many milliliters of 0.550 M hydriodic acid are needed to react with 5.00 mL of 0.217 M CsOH?
HI(aq) + CsOH(aq) → CsI(aq) + H2O(l)
A) 0.0789 mL
B) 0.507 mL
C) 1.97 mL
D) 12.6 mL
71) In an acid-base neutralization reaction 43.74 mL of 0.500 M potassium hydroxide reacts with 50.00 mL
of sulfuric acid solution. What is the concentration of the H2SO4 solution?
A) 0.219 M
B) 0.437 M
C) 0.875 M
D) 1.14 M
72) Balance the chemical equation given below, and determine the number of milliliters of 0.00300 M
phosphoric acid required to neutralize 25.00 mL of 0.00150 M calcium hydroxide.
________ Ca(OH)2(aq) + ________ H3PO4(aq) → ________ Ca3(PO4)2(aq) + ________ H2O(l)
A) 1.69 mL
B) 8.33 mL
C) 12.5 mL
D) 18.8 mL
73) When 220. mL of 1.50 × 10–4 M hydrochloric acid is added to 125 mL of 1.75 × 10-4 M Mg(OH)2, the
resulting solution will be
A) acidic.
B) basic
C) neutral.
D) It is impossible to tell from the information given.
4.3 Short Answer Questions
1) What is the molarity of a solution prepared by dissolving 0.80 g of NaOH in enough water to make 250
mL of solution?
2) The number of moles of CaCl2 in 25.0 mL of 0.222 M CaCl2 is ________.
3) The number of grams of NaCl required to prepare 500 mL of 0.100 M NaCl is ________.
4) The number of milliliters of 12.0 M HCl required to prepare 250 mL of 0.500 M HCl is ________.
5) What is the molarity of a solution prepared by diluting 25 mL of 2.0 M HCl with enough water to make
250 mL of solution?
6) CH3CO2H is an example of a ________ electrolyte.
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7) Assuming complete dissociation, the molar concentration of Br– ions in 0.500 M BaBr2 is ________.
8) The reaction shown below is classified as a(n) ________ reaction.
AgNO3(aq) + HCl(aq) → AgCl(s) + HNO3(aq)
9) The reaction shown below is classified as a(n) ________ reaction.
Pb(OH)2(s) + 2 HNO3(aq) → Pb(NO3)2(aq) + 2 H2O(l)
10) The balanced net ionic equation for the reaction Li2SO4(aq) + Ca(NO3)2(aq) → CaSO4(s) + 2 LiNO3(aq)
is ________.
11) The balanced net ionic equation for the reaction H2SO4(aq) + 2 KOH(aq) → K2SO4(aq) + 2 H2O(l) is
________.
12) The compound K2CO3 is predicted to be soluble based on the solubility guideline that all ________
are soluble.
13) When NaOH(aq) is mixed with CuSO4(aq) a precipitate forms. Based on solubility guidelines the
formula of the precipitate is ________.
14) What are the two products of the reaction H3PO4(aq) + 3 KOH(aq) → ?
15) The hydrogen ion, H+, is also referred to as a ________, and a hydrated hydrogen ion, H3O+, is called
a ________ ion.
16) Because it forms some H+ and OCl– ions when dissolved in water, the molecule HOCl is classified as
a(n) ________.
17) For the following reaction, the acid is ________ and the base is ________.
CH3CO2H(aq) + Ca(OH)2(aq) → Ca(CH3CO2)2(aq) + 2 H2O(l)
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18) The acids HNO3 and HNO2 are named ________ and ________, respectively.
19) The number of milliliters of 0.250 M HCl required to react with 100.0 mL of 0.450 M NaOH in the
reaction shown below is ________.
HCl + NaOH → H2O + NaCl
20) The oxidation number of hydrogen in CaH2 is ________.
21) The oxidation number of chromium in Ag2Cr2O7 is ________.
22) The substance is undergoing oxidation in the reaction below is ________.
2 S2O32-(aq) + I3–(aq) → S4O62-(aq) + 3 I–(aq)
23) In the following reaction, the reducing agent is ________.
2 MnO4–(aq) + 10 Br–(aq) + 16 H+(aq) → 2 Mn2+(aq) +5 Br2(aq) + 8 H2O(aq)
24) The best oxidizing agents are found at the ________ of the activity series.
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25) Metals that do not dissolve in non-oxidizing acids are found at the ________ of the activity series.
26) Metals that do not react with hydrochloric acid to produce hydrogen gas are found ________ H2 in
the activity series.
27) The reaction Cu(s) + 2 HCl(aq) → CuCl2(aq) + H2(g) is predicted not to occur because Cu is ________
than H+ in the activity series.