L84
Chapter
4
Types of Chemical Reactions and Solution Stoichiometry
71. Hydrochloric acid (75.0 mL of 0.250 I[l is added to 225.0 mL
of 0.0550 M Ba(OH)2 solution. What is the concentration of
the excess H+ or OH- ions left in this solution?
72.
A
shrdent mixes four reagents together, thilking that the solutions will neutralize each other. The solutions mixed together are
50.0 mL of 0. 100 M hydrochloric acid, 100.0 mL of 0.200 M of
nitric acid, 500.0 mL of 0.0100 M calcitm hydroxide, and
200.0 mL of 0.100 M rubidium hydroxide. Did the acids and
bases exactly neutralize each other? If not, calculate the concentration of excess H+ or OH- ions left in solution.
7-i.
74.
A 25.00-mL
sample of hydrochloric acid solution requires
24.16 mL of 0.106 M sodium hydroxide for complete neutralization. What is the concentration of the original hydrochloric
acid solution?
A 10.00-mL sample of vinegar, an aqueous solution of acetic
acid (HC2H3O2), is titrated with 0.5062 M NaOH, and
16.58 mL is required to reach the equivalence point.
a.
What is the molarity of the acetic acid?
b. If the density of the vinegar is 1.006 g/cm3, what is the
mass percent
of acetic acid in the vinegar?
75. What volume of 0.0200 M calcium hydroxide is required to
neutralize 35.00 mL of 0.0500 M nitric acid?
76. A 30.0-mL sample of an unknown strong base is neutralized
after the addition of 12.0 mL of a 0.150 M HNO3 solution. If
the unknown base concentration is 0.0300
sible identities for the unknown base.
M,
give some pos-
77, A student tiffates
an unknown amount of potassium hydrogen
phthalate (KHCsH4O1, often abbreviated KHP) with 20.46 mL
204.22 gl
of a 0.1000-M NaOH solution. KHP (molar mass
mol) has one acidic hydrogen. What mass of KHP was titrated
(reacted completely) by the sodium hydroxide solution?
:
78. The concentration of a certain sodium hydroxide solution
was
determined by using the solution to titrate a sample of potassium hydrogen phthalate (abbreviated as KHP). KHP is an acid
with one acidic hydrogen and a molar mass of 204.22 g/mol. In
the tiffation, 34.67 rnL of the sodium hydroxide solution was
required to react with 0.1082 g KHP. Calculate the molarity of
the sodium hydroxide.
Oxi datio
n
-
Red ucti
o
n
'it)" Assign oxidation
for all atoms in each of the following
compounds.
a. KMnOa
b. Nio2
c. NaaFe(OH)6
d. (NH4)2HPO4
e.
PaO6
f.
Fe3Oa
g. XeOFa
h. sFl
i. co
j. c6H1206
80. Assign oxidation states for
a1l atoms
compounds.
a.
b.
UO22+
c.
d.
e.
NaBiO3
As2O3
Asa
HAsO2
f.
g.
h.
i.
Mg2P2O7
Na2S2O3
,
Asbign the oxidation state for nitrogen in each of the following.
a. Li3N
b. NH3
c. N2Ha
d. No
e. N2O
f.
No2
B.
NOz
h. No3-
i.
Nz
82. Assign oxidation numbers to all the
atoms
in
each
of
the
following.
a. SrCr2OT
b. CuC1z
c. O:
d. Hrol
e. MgCO3
f'
g.
PbSO3
h.
Pbo2
i.
Na2C2Oa
j.
Ag
Coz
k.
(NHa)2Ce(SOa)3
l.
CrzO:
83. Specify which ofthe following
are oxidation-reduction reac-
tions. and identify the oxidizing agent, the reducing agent, the
substance being oxidized, and the substance being reduced.
a.
b.
c.
d.
e.
Cu(s)
-
+
2Ag-(aq) -+2Ag(s)
Cu2*(aq)
HClk) + NH3k)-+NHaCl(s)
+ 2Hro0) --+4HCl(aq) + SiOr(s)
SiCl4(1) + 2Mg(s)-+2MgC12(s) + Si(s)
el(oH)-' (aq) --+ Ato2@q) + zuro(t)
SiCtr(/)
84. Specifu which of the following
equations represent oxidation-
reduction reactions. and indicate the oxidizing agent, the reducing agent. the species being oxidized, and the species being reduced.
a. cH.Q) + H:o(s)-+co(s) + 3Hr(s)
b. 2A-eNOs(cq) + Cu(s)--+Cu(NO)r(aq) + 2Ag(s)
c. Zn(s) + 2HCt(aq) --+ZnCl2@q) + Hr(s)
d. ZH'=(aq) + 2CrOo2-(aq) --+Cr2O72-(aa) + urO(l)
85. Consider the reaction between sodium metal and fluorine (F1
gas to forrn sodium fluoride. Using oxidation states, hcm
many electrons wouid each sodium atom lose, and how ma4
electrons *'ould each fluorine atom gain? How many sodi'.tnn
atoms are needed to react with one fluorine molecule? Writt.ur
balanced equation for this reaction.
86. Consider the reaction between oxygen (O2) gas and magx.-
Reacti o n s
states
tll
sium metal to form magnesium oxide. Using oxidation sta.res,*
how many electrons would each oxygen atom gain, and trmi
many electrons would each magnesium atom lose? How m.nry'
magnesium atoms are needed to react with one oxlgen mr'F
cule? Write a balanced equation for this reaction.
87. Balance each of the following oxidation-reduction
by using the oxidation states method.
in each of the following
a.
b.
c.
d.
C,Hufu) + or(s)-+Cor(s) + HrO(s)
Me(s) + HCI(aq) --+Mg2+(aq) + Cr-(aq)
+
Ni2+(aq)
Zn(s) + H2Soo(aq) -->ZnSOo@q)
+ Hr(s)
Co3-(aq) + Ni(s) -->Co2*(aq)
+
Hr(g)
88. Balance each of the following oxidation-reduction reacn
Hg2C12
by using the oxidation states method.
Ca(NO3)2
a. Clrk) + Ai(s) --+A13*(aq) + Cr-(aq)
b. or(s) + Hro(l) + Pb(s)--+ru(on)r(s)
c. H*(aq) + Mno. (aq) * Fe2+(aq) -->
Mn2* (aq) + Fe3+ (aq) +
r.jnless
ori..yrite nole{j. !ll art
on this page js O Cen?a;t+,
H
e:-
=