64. A 170.0-g sample of metal at 79.00°C is added to 170.0 g of H2O(l) at 14.00°C in an
insulated container. The temperature rises to 16.19°C. Neglecting the heat capacity of the
container, what is the specific heat of the metal? The specific heat of H2O(l) is 4.18
J/(g · °C).
A)
4.18 J/(g · °C)
B)
120 J/(g · °C)
C)
0.146 J/(g · °C)
D)
–0.146 J/(g · °C)
E)
28.6 J/(g · °C)
65. Exactly 105.2 J will raise the temperature of 10.0 g of a metal from 25.0°C to 60.0°C. What
is the specific heat capacity of the metal?
A)
0.301 J/(g · °C)
B)
3.33 J/(g · °C)
C)
29.3 J/(g · °C)
D)
25.2 J/(g · °C)
E)
none of these
66. A 85.9-g piece of cobalt (s = 0.421 J/(g · °C)), initially at 263.1°C, is added to 116.2 g of a
liquid, initially at 24.7°C, in an insulated container. The final temperature of the metal–
liquid mixture at equilibrium is 50.8°C. What is the identity of the liquid? Neglect the heat
capacity of the container.
A)
hexane (s = 2.27 J/(g · °C))
B)
methanol (s = 2.53 J/(g · °C))
C)
acetone (s = 2.15 J/(g · °C))
D)
ethanol (s = 2.43 J/(g · °C))
E)
water (s = 4.18 J/(g · °C))
Test Bank General Chemistry, 10th edition 22
67. A 42.9-g sample of cobalt (s = 0.421 J/(g · °C)), initially at 157.2°C, is placed in an
insulated vessel containing 120.9 g of water (s = 4.18 J/(g · °C)), initially at 19.2°C. Once
equilibrium is reached, what is the final temperature of the metal–water mixture? Neglect
the heat capacity of the vessel.
A)
24.0°C
B)
55.3°C
C)
14.1°C
D)
88.2°C
E)
31.8°C
68. How much heat must be applied to a 18.3-g sample of iron (s = 0.449 J/(g · °C)) in order to
raise its temperature from 23.8°C to 356.6°C?
A)
2.93 103 J
B)
2.73 103 J
C)
1.96 102 J
D)
6.09 103 J
E)
1.49 102 J
69. A 94.7-g sample of silver (s = 0.237 J/(g · °C)), initially at 348.25°C, is added to an
insulated vessel containing 143.6 g of water (s = 4.18 J/(g · °C)), initially at 13.97°C. At
equilibrium, the final temperature of the metal–water mixture is 22.63°C. How much heat
was absorbed by the water? The heat capacity of the vessel is 0.244 kJ/°C.
A)
5.20 kJ
B)
3.09 kJ
C)
7.31 kJ
D)
9.12 kJ
E)
129 kJ
70. A 500-cm3 sample of 1.0 M NaOH(aq) is added to 500 cm3 of 1.0 M HCl(aq) in a
Styrofoam cup, and the solution is quickly stirred. The rise in temperature (T1) is
measured. The experiment is repeated using 100 cm3 of each solution, and the rise in
temperature (T2) is measured. What conclusion can you draw about T1 and T2?
HCl(aq) + NaOH(aq) → H2O(l) + NaCl(aq); H° = –55.8 kJ
Test Bank General Chemistry, 10th edition 23
A)
T2 is greater than T1.
B)
T2 is equal to T1.
C)
T1 is five times as large as T2.
D)
T1 is less than T2.
E)
T2 is five times as large as T1.
71. In a bomb calorimeter, reactions are carried out
A)
at 1 atm pressure and 0°C.
B)
at a constant pressure.
C)
at a constant volume.
D)
at a constant pressure and 25°C.
E)
at 1 atm pressure and 25°C.
72. A bomb calorimeter has a heat capacity of 2.47 kJ/K. When a 0.105-g sample of a certain
hydrocarbon was burned in this calorimeter, the temperature increased by 2.14 K. Calculate
the energy of combustion for 1 g of the hydrocarbon.
A)
–5.29 J/g
B)
−5.03 105
J/g
C)
–0.120 J/g
D)
−2.35 103
J/g
E)
–0.560 J/g
73. When 7.13 g of methane (CH4) is burned in a bomb calorimeter (heat capacity =
2.677 103 J/°C), the temperature rises from 24.00 to 27.08°C. How much heat is absorbed
by the calorimeter?
CH4(g) + 2O2(g) → CO2(g) + 2H2O(l); H° = –1283.8 kJ
A)
562 kJ
B)
3.66 103 kJ
C)
8.24 kJ
D)
571 kJ
E)
1.28 103 kJ
Test Bank General Chemistry, 10th edition 24
74. When 0.0600 mol of HCl(aq) is reacted with 0.0600 mol of NaOH(aq) in 50.0 mL of water,
the temperature of the solution increases by 15.1°C. What is the enthalpy of reaction for the
following thermochemical equation?
HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
Assume that the heat capacity of the solution and calorimeter is 221.3 J/°C.
A)
–0.201 kJ
B)
55.8 kJ
C)
–3.35 kJ
D)
–55.8 kJ
E)
3.35 kJ
75. When 50.0 mL of 1.20 M of HCl(aq) is combined with 50.0 mL of 1.30 M of NaOH(aq) in
a coffee-cup calorimeter, the temperature of the solution increases by 8.01°C. What is the
change in enthalpy for this balanced reaction?
HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
Assume that the solution density is 1.00 g/mL and the specific heat capacity of the solution
is 4.18 J/gC.
A)
–55.8 kJ
B)
55.8 kJ
C)
51.5 kJ
D)
–51.5 kJ
E)
–26.8 kJ
76. Combustion of 7.21 g of liquid benzene (C6H6) causes a temperature rise of 50.3°C in a
constant-pressure calorimeter that has a heat capacity of 5.99 kJ/°C. What is H for the
following reaction?
C6H6(l) + O2(g) → 6CO2(g) + 3H2O(l)
A)
–302 kJ/mol
B)
41.8 kJ/mol
C)
–41.8 kJ/mol
D)
–3.27 103 kJ/mol
E)
302 kJ/mol
77. Given:
Pb(s) + PbO2(s) + 2H2SO4(l) → 2PbSO4(s) + 2H2O(l); H° = –509.2 kJ
SO3(g) + H2O(l) → H2SO4(l); H° = –130. kJ
determine H° for the following thermochemical equation.
Pb(s) + PbO2(s) + 2SO3(g) → 2PbSO4(s)
A)
3.77 103 kJ
B)
–521 kJ
C)
–3.77 103 kJ
D)
–639 kJ
E)
–769 kJ
78. Given:
Fe2O3(s) + 3CO(g) → 2Fe(s) + 3CO2(g); H° = –26.8 kJ
FeO(s) + CO(g) → Fe(s) + CO2(g); H° = –16.5 kJ
determine H° for the following thermochemical equation.
Fe2O3(s) + CO(g) → 2FeO(s) + CO2(g)
A)
6.2 kJ
B)
10.3 kJ
C)
22.7 kJ
D)
–10.3 kJ
E)
–43.3 kJ
79. The overall chemical equation resulting from the sum of the following three steps is
2C(s) + 2H2O(g) → 2CO(g) + 2H2(g)
CO(g) + H2O(g) → CO2(g) + H2(g)
CO(g) + 3H2(g) → CH4(g) + H2O(g)
A)
2C(s) + 2H2O(g) → CO2(g) + CH4(g)
B)
2C(s) + 3H2O(g) → CO(g) + CO2(g) + 3H2(g)
C)
2C(s) + H2O(g) + H2(g)→ CO(g) + CH4(g)
D)
2CO(g) + 2H2(g) → CH4(g) + CO2(g)
E)
2C(s) + CH4(g) + 3H2O(g) → CO(g) + 5H2(g)
80. Using the following data, calculate the standard enthalpy of reaction for the coal gasification
process 2C(s) + 2H2O(g) → CH4(g) + CO2(g).
C(s) + H2O(g) → CO(g) + H2(g); H° = +131.3 kJ
CO(g) + H2O(g) → CO2(g) + H2(g); H° = –41.2 kJ
CO(g) + 3H2(g) → CH4(g) + H2O(g); H° = –206.1 kJ
A)
–116.0 kJ
B)
378.6 kJ
C)
+15.3 kJ
D)
–157.2 kJ
E)
–378.6 kJ
81. Given the following data, calculate the standard enthalpy of reaction for the conversion of
buckminsterfullerene (C60) into diamond:
C(graphite) → C(diamond); H° = +1.897 kJ
60C(graphite) → C60(fullerene); H° = +2193 kJ
A)
-35 kJ
B)
35 kJ
C)
−2191 kJ
D)
2191 kJ
E)
38 kJ
Test Bank General Chemistry, 10th edition 27
82. Using two or more of the following,
N2(g) + O2(g) → N2O3(s); H° = 83.7 kJ
N2(g) + O2(g) → 2NO(g); H° = 180.4 kJ
N2(g) + O2(g) → NO2(g); H° = 33.2 kJ
N2(g) + H2(g) → NH3(g); H° = −45.9 kJ
determine H° for the following reaction.
NO(g) + NO2(g) → N2O3(g)
A)
–39.7 kJ
B)
24.3 kJ
C)
–207.1 kJ
D)
39.7 kJ
E)
207.1 kJ
83. Consider the following changes at constant temperature and pressure:
H2O(s) → H2O(l); H1
H2O(l) → H2O(g); H2
H2O(g) → H2O(s); H3
Using Hess’s law, the sum H1 + H2 + H3 is
A)
equal to zero.
B)
sometimes greater than zero and sometimes less than zero.
C)
less than zero.
D)
cannot be determined without numerical values for H.
E)
greater than zero.
84. Given the following thermochemical data at 25°C and 1 atm pressure,
O2(g) + 2B(s) → B2O3(s); H° = –1264 kJ
O3(g) + 2B(s) → B2O3(s); H° = –1406 kJ
determine H° for the following reaction at 25°C and 1 atm pressure.
3O2(g) → 2O3(g)
A)
–980 kJ/mol
B)
+284 kJ/mol
C)
+980 kJ/mol
D)
–2670 kJ/mol
E)
–284 kJ/mol
85. What is the standard enthalpy of formation of liquid methylamine (CH3NH2)?
C(s) + O2(g) → CO2(g); H° = –393.5 kJ
2H2O(l) → 2H2(g) + O2(g); H° = 571.6 kJ
N2(g) + O2(g) → NO2(g); H° = 33.10 kJ
4CH3NH2(l) + 13O2(g) → 4CO2(g) + 4NO2(g) + 10H2O(l); H° = –4110.4 kJ
A)
+3899.2 kJ/mol
B)
–3899.2 kJ/mol
C)
–47.3 kJ/mol
D)
+47.3 kJ/mol
E)
+3178.4 kJ
86. Given that
O(g) + e– → O–(g); H = –142 kJ
O(g) + 2e– → O2–(g); H = 702 kJ
the enthalpy change for the reaction represented by the equation
O–(g) + e– → O2–(g) is
A)
0 kJ.
B)
–560 kJ.
C)
–844 kJ.
D)
844 kJ.
E)
560 kJ.
87. Which of the following has a standard enthalpy of formation value of zero at 25°C?
A)
Cl(g)
B)
Cl2(l)
C)
Cl2(g)
D)
Cl(s)
E)
Cl2(s)
88. Which of the following has a standard enthalpy of formation value of zero at 25°C?
A)
O2(g)
B)
O3(g)
C)
O2(l)
D)
O(g)
E)
O2(s)
89. All of the following have a standard enthalpy of formation value of zero at 25°C except
A)
C(s).
B)
Ne(g).
C)
Fe(s).
D)
F2(g).
E)
CO(g).
90. Which substance has a standard enthalpy of formation equal to zero at 25°C?
A)
C2H6(g)
B)
Br2(g)
C)
Br2(l)
D)
Br2(s)
E)
C2H6(l)
Test Bank General Chemistry, 10th edition 30
91. Which of the following species does not have a standard enthalpy of formation equal to zero
at 25°C?
A)
Cl2(l)
B)
N2(g)
C)
Fe(s)
D)
H+(aq)
E)
S8(s)
92. Which of the following has a standard enthalpy of formation value of zero at 25°C?
A)
C6H12O6(s)
B)
S8(s)
C)
FeSO4(s)
D)
H2O(l)
E)
FeSO4(aq)
93. Which of the following reactions corresponds to the thermochemical equation for the
standard enthalpy of formation of solid lead (II) nitrate?
A)
Pb2+(aq) + 2NO3–(aq) → Pb(NO3)2(s)
B)
Pb(OH)2(s) + 2HNO3(aq) → Pb(NO3)2(s) + 2H2O(l)
C)
Pb(s) + N2(g) + 3O2(g) → Pb(NO3)2(s)
D)
Pb(s) + 2HNO3(aq) → Pb(NO3)2(s) + H2(g)
E)
Pb(s) + 2N(g) + 6O(g) → Pb(NO3)2(s)
94. The standard enthalpy change for which of the following processes corresponds to the
standard enthalpy of formation of solid cesium fluoride?
A)
Cs(s) + F2(s) → CsF(s)
B)
Cs(g) + F2(g) → CsF(g)
C)
Cs(g) + F(g) → CsF(s)
D)
Cs(s) + F2(g) → CsF(s)
E)
Cs(s) + F2(s) → CsF(g)
95. The enthalpy change at 1 atm of which reaction corresponds to the standard enthalpy of
formation of solid potassium bromate, KBrO3?
A)
K(s) + Br(g) + 3O(g) → KBrO3(s)
B)
K(g) + Br(g) + 3O(g) → KBrO3(s)
C)
K(g) + Br2(g) + O2(g) → KBrO3(s)
D)
K(s) + Br2(l) + O2(g) → KBrO3(s)
E)
K(s) + Br2(g) + O2(g) → KBrO3(s)
96. For which of the following equations is the enthalpy change at 1 atm pressure equal to the
standard enthalpy of formation of liquid formic acid, HCOOH?
A)
C(g) + 2H(g) + 2O(g) → HCOOH(l)
B)
C(s) + 2H(g) + 2O(g) → HCOOH(l)
C)
C(s) + H2(g) + O2(g) → HCOOH(l)
D)
CO(g) + H2O(l) → HCOOH(l)
E)
CO2(g) + H2(g) → HCOOH(l)
97. The balanced equation representing the standard enthalpy of formation reaction for NH3(g)
is
A)
N(g) + H2(g) → NH3(g).
B)
N2(g) + 3H(g) → NH3(g).
C)
N(g) + 3H(g) → NH3(g).
D)
N2(g) + H2(g) → NH3(g).
E)
N2(g) + H2(g) → NH3(g).
98. The enthalpy change at 1 atm of which reaction corresponds to the standard enthalpy of
formation of solid magnesium nitrate, Mg(NO3)2?
A)
Mg2+(g) + 2NO3–(g) → Mg(NO3)2(s)
B)
Mg(s) + N2(g) + 3O2(g) → Mg(NO3)2(s)
C)
Mg(g) + 2N(g) + 6O(g) → Mg(NO3)2(s)
D)
Mg(s) + N2(g) + 2O3(g) → Mg(NO3)2(s)
E)
Mg2+(aq) + 2NO3–(aq) → Mg(NO3)2(s)
99. Which of the following reactions corresponds to the thermochemical equation for the
standard enthalpy of formation of N,N-diethyl-m-toluamide, C12H17NO(l), the active
ingredient in some insect repellents?
A)
12C(l) + 17H(l) + N(l) + O(l) → C12H17NO(l)
B)
12C(g) + 17H(g) + N(g) + O(g) → C12H17NO(g)
C)
12C(s) + 17H(g) + N(g) + O(g) → C12H17NO(l)
D)
12C(s) + H2(g) + N2(g) + O2(g) → C12H17NO(l)
E)
12C(g) + 17H(g) + N(g) + O(g) → C12H17NO(l)
100. What is H° for the following phase change?
KCl(s) → KCl(l)
Substance
H°f (kJ/mol)
KCl(s)
–436.68
KCl(l)
–421.79
A)
858.47 kJ
B)
14.89 kJ
C)
–858.47 kJ
D)
–14.89 kJ
E)
0 kJ
Test Bank General Chemistry, 10th edition 33
101. A 34.5-L sample of a gaseous hydrocarbon, measured at 1.00 atm pressure and 25.0°C, is
burned in excess oxygen, liberating 2.20 103 kJ of heat at constant pressure. What is the
identity of the hydrocarbon? (R = 0.0821 L · atm/(K · mol))
Substance
H°f (kJ/mol)
CO2(g)
–393.5
H2O(l)
–285.8
A)
propylene (C3H6, H°f = 20.41 kJ/mol)
B)
ethylene (C2H4, H°f = 52.47 kJ/mol)
C)
acetylene (C2H2, H°f = 226.73 kJ/mol)
D)
ethane (C2H6, H°f = –84.68 kJ/mol)
E)
propane (C3H8, H°f = –104.7 kJ/mol)
102. What is H° of the following reaction?
CO2(g) + 2CH4(g) → C3H8(g) + O2(g)
Substance
H°f (kJ/mol)
CO2(g)
–393.5
CH4(g)
–74.9
C3H8(g)
–104.7
A)
–348.4 kJ
B)
–573.1 kJ
C)
438.6 kJ
D)
348.4 kJ
E)
–648.0 kJ
103. From the following information, determine H°f of malonic acid, CH2(COOH)2(s).
CH2(COOH)2(s) + 2O2(g) → 3CO2(g) + 2H2O(l); H° = –861.0 kJ
Substance
H°f (kJ/mol)
CO2(g)
–393.5
H2O(l)
–285.8
A)
2613 kJ
B)
891.1 kJ
C)
−1540.3 kJ
D)
−2613.1 kJ
E)
−891.1 kJ
104. At 25°C, when 1.00 g of sulfur is burned at constant pressure in excess oxygen to give
SO2(g), 9.28 kJ of heat is liberated. What is the enthalpy of formation of SO2(g)?
A)
9.28 kJ/mol
B)
–594 kJ/mol
C)
298 kJ/mol
D)
–9.28 kJ/mol
E)
–298 kJ/mol
105. What is the standard enthalpy of formation of liquid butyraldehyde, CH3CH2CH2CHO(l)?
CH3CH2CH2CHO(l) + O2(g) → 4H2O(l) + 4CO2(g); H° = –2471.8 kJ
Substance
H°f (kJ/mol)
CO2(g)
–393.5
H2O(l)
–285.8
A)
–245.4 kJ/mol
B)
+245.4 kJ/mol
C)
–1792.5 kJ/mol
D)
–3151.1 kJ/mol
E)
+3151.1 kJ/mol
Test Bank General Chemistry, 10th edition 35
106. What is H° for the following reaction?
2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(l)
Substance
H°f (kJ/mol)
C2H2(g)
+226.7
CO2(g)
–393.5
H2O(l)
–285.8
A)
+1692.2 kJ
B)
–452.6 kJ
C)
–1692.2 kJ
D)
+2599.0 kJ
E)
–2599.0 kJ
107. What is the standard enthalpy change for the combustion of gaseous propylene, C3H6?
C3H6(g) + O2(g) → 3CO2(g) + 3H2O(l)
Substance
H°f (kJ/mol)
C3H6(g)
+20.4
CO2(g)
–393.5
H2O(l)
–285.8
A)
+2017.5 kJ
B)
–2058.3 kJ
C)
–658.9 kJ
D)
–2017.5 kJ
E)
+2058.3 kJ
108. What is the standard enthalpy of formation of liquid n-butanol, CH3CH2CH2CH2OH?
CH3CH2CH2CH2OH(l) + 6O2(g) → 4CO2(g) + 5H2O(l); H° = –2675 kJ
Substance
H°f (kJ/mol)
CO2(g)
–393.5
H2O(l)
–285.8
Test Bank General Chemistry, 10th edition 36
A)
–328 kJ
B)
+3355 kJ
C)
–1996 kJ
D)
+328 kJ
E)
–3355 kJ
109. At 25°C, the standard enthalpy of combustion of gaseous propane (C3H8) is –2219.0 kJ per
mole of propane, and the standard enthalpy of combustion of gaseous propylene (C3H6) is –
2058.3 kJ per mole of propylene. What is the standard enthalpy change for the following
reaction at 25°C?
C3H6(g) + H2(g) → C3H8(g)
Substance
H°f (kJ/mol)
CO2(g)
–393.5
H2O(l)
–285.8
A)
+104.7 kJ
B)
–20.4 kJ
C)
–125.1 kJ
D)
+160.7 kJ
E)
–160.7 kJ
110. What is the standard enthalpy change for the combustion of liquid cyclopentane, C5H10?
2C5H10(l) + 15O2(g) → 10CO2(g) + 10H2O(l)
Substance
H°f (kJ/mol)
C5H10(l)
–105.6
CO2(g)
–393.5
H2O(l)
–285.8
A)
+573.7 kJ
B)
–573.7 kJ
C)
+784.9 kJ
D)
–784.9 kJ
E)
–6581.8 kJ
111. What is the standard enthalpy change for the following reaction?
3CH4(g) + 4O3(g) → 3CO2(g) + 6H2O(g)
Substance
H°f (kJ/mol)
CH4(g)
–74.87
O3(g)
+142.7
CO2(g)
–393.5
H2O(g)
–241.8
A)
–2285.1 kJ
B)
–2977.5 kJ
C)
+2977.5 kJ
D)
+2285.1 kJ
E)
–3426.5 kJ
112. What is the standard enthalpy change for the following reaction?
N2H4(l) + 2NO2(g) → 2N2O(g) + 2H2O(l)
Substance
H°f (kJ/mol)
N2H4(l)
+50.6
NO2(g)
+33.1
N2O(g)
+82.1
H2O(l)
–285.8
A)
–290.6 kJ
B)
–524.2 kJ
C)
–119.7 kJ
D)
+290.6 kJ
E)
+119.7 kJ
Test Bank General Chemistry, 10th edition 38
113. What is the standard enthalpy of formation of liquid diethylamine, (CH3CH2)2NH?
N2O5(g) + 8CH4(g) → 2(CH3CH2)2NH(l) + 5H2O(l); H° = –1103 kJ
Substance
H°f (kJ/mol)
N2O5(g)
+11.3
CH4(g)
–74.9
H2O(l)
–285.8
A)
–131 kJ/mol
B)
–421 kJ/mol
C)
+131 kJ/mol
D)
–1452 kJ/mol
E)
+421 kJ/mol
114. The standard enthalpies of formation of various iodine species are as follows:
Substance
H°f (kJ/mol)
I(g)
+107
I2(g)
+21
HI(g)
+26
What additional information is needed to calculate the standard enthalpy change of the
following reaction?
H2(g) + I2(g) → 2HI(g)
A)
none, because the answer is 2 times 26 kJ/mol
B)
the enthalpy of formation of I−(g) and H+(g)
C)
the enthalpy of formation of solid iodine
D)
none, because the enthalpy of formation of I2(g) and HI(g) are given and the
enthalpy of elemental hydrogen is zero
E)
the enthalpy of formation of gaseous hydrogen
115. What is the standard enthalpy of formation of MgCO3(s)?
MgO(s) + CO2(g) → MgCO3(s); H° = –100.7 kJ
Substance
H°f (kJ/mol)
MgO(s)
–601.6
CO2(g)
–393.5
Test Bank General Chemistry, 10th edition 39
A)
107.4 kJ
B)
–308.8 kJ
C)
–894.4 kJ
D)
–1095.8 kJ
E)
894.4 kJ
116. From the following information, determine the enthalpy of formation of C2H4(g).
C2H4(g) → C(s) + H2(g); H = –26.2 kJ
A)
–26.2 kJ/mol
B)
26.2 kJ/mol
C)
104.8 kJ/mol
D)
–52.4 kJ/mol
E)
52.4 kJ/mol
117. Calculate the change in enthalpy when 52.0 g of solid chromium at 25°C and 1 atm pressure
is oxidized. (H°f for Cr2O3(s) is –1135 kJ/mol.)
4Cr(s) + 3O2(g) → 2Cr2O3(s)
A)
–1135 kJ
B)
–284 kJ
C)
–568 kJ
D)
+1135 kJ
E)
+568 kJ
118. Which of the following is/are correct about fossil fuels?
1.
Anthracite coal is pure, amorphous carbon.
2.
Purified natural gas is a mixture of primarily methane and small amounts of
ethane, propane, and butane.
3.
Gasoline obtained from petroleum primarily contains the hydrocarbon octane
(C8H18).
A)
1 only
B)
2 only
C)
3 only
D)
1, 2 and 3
E)
none
119. Which of the following is not a fuel–oxidizer mixture used in rockets?
A)
kerosene–oxygen
B)
hydrogen–oxygen
C)
octane–oxygen
D)
aluminum–ammonium perchlorate
E)
hydrazine–dinitrogen tetroxide