CHAPTER
13
SOLUTIONS MANUAL
Gases
Section 13.1 The Gas Laws
Problem-Solving Lab
pages 442–451
page 444
Practice Problems
Ribs
page 443
Assume that the temperature and the amount of
gas are constant in the following problems.
1. The volume of a gas at 99.0 kPa is 300.0 mL. If
the pressure is increased to 188 kPa, what will
be the new volume?
Lungs
158 mL
V2 V P
(300.0 mL)(99.0 kPa)
_
__ 158 mL
1 1
P2
188 kPa
2. The pressure of a sample of helium in a
1.00-L container is 0.988 atm. What is the new
pressure if the sample is placed in a 2.00-L
container?
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
0.494 atm
P2 V P
(1.00 L)(0.988 atm)
_
__ 0.494 atm
1 1
V2
2.00 L
3. Challenge Air trapped in a cylinder fitted
with a piston occupies 145.7 mL at 1.08 atm
pressure. What is the new volume when the
piston is depressed, increasing the pressure
by 25%?
117 mL
P2 1.08 atm (1.08 atm 0.25) 1.35 atm
V2 V P
(145.7 mL)(1.08 atm)
_
__ 117 mL
1 1
P2
1.35 atm
Diaphragm
1. Apply Boyle’s law to explain why air enters
your lungs when you inhale and leaves when
you exhale.
Boyle’s Law states that at constant temperature,
the volume of a gas varies inversely with
pressure. When you inhale, lung volume
increases. Pressure decreases and air moves
in. When you exhale, lung volume decreases.
Pressure increases and air moves out.
2. Explain what happens inside the lungs when
a blow to the abdomen knocks the wind out of
a person. Use Boyle’s law to determine your
answer.
When someone is hit in the abdomen, the
diaphragm is temporarily paralyzed. When the
diaphragm does not move up and down, lung
volume does not change. If the volume does not
change, pressure inside the lungs does not change,
and air is not drawn in and out of the lungs.
3. Infer Parts of the lungs lose elasticity and
become enlarged when a person has emphysema.
From what you know about Boyle’s law, why
does this condition affect breathing?
If parts of the lungs lose elasticity, it is more
difficult to change lung volume. With less change
in volume, there is less difference in pressure.
With less difference in pressure, it is more difficult
for air to enter or exit the lungs.
Solutions Manual
Chemistry: Matter and Change • Chapter 13
253
CHAPTER
13
SOLUTIONS MANUAL
4. Explain why beginning scuba divers are taught
7. Challenge A gas occupies 0.67 L at 350 K.
never to hold their breath while ascending from
deep water.
What temperature is required to reduce the
volume by 45%?
As a scuba diver ascends, pressure decreases.
A decrease in pressure results in an increase
in volume. If a diver holds his or her breath
while ascending, air volume in the lungs would
increase.
190 K
V2 0.67 L (0.67 L 0.45) 0.37 L
T2 T V
(350 K)(0.37 L )
_
__ 190 K
1 2
V1
0.67 L
Assume that the volume and the amount of gas
are constant in the following problems.
Practice Problems
pages 446–450
4. What volume will the gas in the balloon below
occupy at 250 K?
8. The pressure in an automobile tire is 1.88 atm
at 25.0°C. What will be the pressure if the
temperature increases to 37.0°C?
1.96 atm
4.3 L
350 K
T1 25.0°C 273 298 K
T2 37.0°C 273 310 K
P2 P T
(1.88 atm)(310 K)
_
__ 1.96 atm
1 2
T1
298 K
3.1 L
V2 V T
(4.3 L)(250 K)
_
__ 3.1 L
1 2
T1
350 K
5. A gas at 89ºC occupies a volume of 0.67 L.
At what Celsius temperature will the volume
increase to 1.12 L?
330°C
T1 89°C 273 362 K
T2 T V
(362 K)(1.12 L)
_
__ 605 K
1 2
V1
0.67 L
605 273 332°C 330°C
6. The Celsius temperature of a 3.00-L sample of
gas is lowered from 80.0ºC to 30.0ºC. What
will be the resulting volume of this gas?
138°C
T2 36.5°C 273 309.5 K
T1 T P
(309.5 K)(1.12 atm)
_
__ 135 K
2 1
P2
2.56 atm
135 K 273 138°C
10. Challenge If a gas sample has a pressure
of 30.7 kPa at 0.00ºC, by how many degrees
Celsius does the temperature have to increase to
cause the pressure to double?
273°C
T1 0.00°C 273 273 K
2.58 L
P2 (30.7 kPa)(2) 61.4 kPa
T1 80.0°C 273 353 K
T2 T2 30.0°C 273 303 K
V2
254
1.12 atm pressure. At 36.5ºC, that same gas
sample has a pressure of 2.56 atm. What
was the initial temperature of the gas in the
cylinder?
V T
(3.00 L)(303 K)
_ __ 2.58 L
T P
(273 K)(61.4 kPa)
_
__ 546 K
1 2
P1
30.7 kPa
546 K 273 273°C
1 2
T1
353 K
Chemistry: Matter and Change • Chapter 13
The temperature must increase by 273°C.
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
9. Helium gas in a 2.00-L cylinder is under
CHAPTER
13
SOLUTIONS MANUAL
Assume that the amount of gas is constant in the
following problems.
11. A sample of air in a syringe exerts a pressure
of 1.02 atm at 22.0ºC. The syringe is placed in
a boiling water-bath at 100.0ºC. The pressure is
increased to 1.23 atm by pushing the plunger in,
which reduces the volume to 0.224 mL. What
was the initial volume?
13. Challenge If the temperature in the gas
cylinder below increases to 30.0°C and the
pressure increases to 1.20 atm, will the
cylinder’s piston move up or down?
0.00°C
0.214 mL
1.00 atm
T1 22.0°C 273 295 K
T2 100.0°C 273 373 K
V1 2 1 2
T2P1
0.214 mL
(373 K)(1.02 atm)
down
12. A balloon contains 146.0 mL of gas confined
at a pressure of 1.30 atm and a temperature of
5.0°C. If the pressure doubles and the
temperature decreases to 2.0°C, what will be
the volume of gas in the balloon?
72 mL
T1 5.0°C 273 278 K
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
T2 2.0°C 273 275 K
V2 30.0 mL
V T P
(0.224 mL)(295 K)(1.23 atm)
_
___
P T V
(1.30 atm)(275 K)(146.0 mL)
_
___
1 2 1
P2T1
72 mL
(2.60 atm)(278 K)
T1 0.00°C 273 273 K
T2 30.0°C 273 303 K
V
P T
(1.00 atm)(303 K)
_
_ __ 0.92
2
1 2
V1
P2T1
(1.20 atm)(273 K)
This is a ratio, so there are no units. 0.92 < 1, so
V2 must be less than V1. The final volume is less
than the original volume, so the piston will move
down.
Section 13.1 Assessment
page 451
14. State the relationship among pressure, tempera-
ture, and volume of a fixed amount of gas.
This relationship is given by the combined gas
law. P1V1/T1 P2V2/T2. For example: when the
temperature increases, either the volume or
pressure increases (or both).
15. Explain Which of the three variables that
apply to equal amounts of gases are directly
proportional? Which are inversely proportional?
P and V are directly proportional to T, and P and
V are inversely proportional to each other.
Solutions Manual
Chemistry: Matter and Change • Chapter 13
255
CHAPTER
13
SOLUTIONS MANUAL
16. Analyze A weather balloon is released into
the atmosphere. You know the initial volume,
temperature, and air pressure. What information will you need to predict the volume when it
reaches its final altitude? Which law would you
use to calculate this volume?
19. Design a concept map that shows the relation-
ship among pressure, volume, and temperature
in Boyle’s, Charles’s, and Gay-Lussac’s laws.
The concept map should show how P, V, and T
are proportional to one another. It should also
label each pair of variables used in the gas laws.
You would need to know the final temperature
and final pressure to calculate the final volume.
Use the combined gas law.
Constant
amount of gas
17. Infer why gases such as the oxygen used
at hospitals are compressed. Why must
compressed gases be shielded from high
temperatures? What must happen to compressed
oxygen before it can be inhaled?
A greater mass confined to a smaller volume
makes transporting and storing of gases easier.
Increasing temperature increases pressure,
and the cylinders might explode. Before
compressed oxygen can be breathed, it must be
decompressed.
Temperature
held constant
Pressure
held constant
Volume
held constant
P1V1 P2V2
V1
V2
T1
T2
Charles’s law
P1
P2
T1
T2
Gay-Lussac’s
law
Boyle’s law
Section 13.2 The Ideal Gas Law
pages 452–459
18. Calculate A rigid plastic container holds
711 torr
T2 44.6°C 273 318 K
P T
(660 torr)(318 K)
_
__ 711 torr
1 2
T1
pages 453–455
20. What size container do you need to hold
0.0459 mol of N2 gas at STP?
1.03 L
T1 22.0°C 273 295 K
P2 Practice Problems
295 K
_
0.0459 mol 22.4 L 1.03 L
1 mol
21. How much carbon dioxide gas, in grams, is in a
1.0-L balloon at STP?
2.0 g
1.0 L 1 mol
_
0.045 mol
22.4 L
0.045 mol 44.0 g
_
2.0 g
1 mol
22. What volume in milliliters will 0.00922 g of H2
gas occupy at STP?
102 mL
0.00922 g 1 mol
_
0.00457 mol
2.02 g
0.00457 mol 256
Chemistry: Matter and Change • Chapter 13
22.4 L
_
0.102 L or 102 mL
1 mol
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
1.00 L of methane gas at 660 torr pressure
when the temperature is 22.0°C. How much
pressure will the gas exert if the temperature is
raised to 44.6°C?
13
CHAPTER
SOLUTIONS MANUAL
23. What volume will 0.416 g of krypton gas
27. Calculate the volume of a 0.323-mol sample of a
occupy at STP?
gas at 265 K and 0.900 atm.
0.111 L
7.81 L
0.416 g 1 mol
_
0.00496 mol
83.80 g
22.4 L
0.00496 mol _ 0.111 L
Latm
(0.323 mol)(0.0821 _
)(265 K)
molK
nRT
_
____
V
P
7.81 L
0.900 atm
1 mol
28. What is the pressure, in atmospheres, of a
24. Calculate the volume that 4.5 kg of ethylene
gas (C2H4) will occupy at STP.
0.108-mol sample of helium gas at a temperature of 20.0ºC if its volume is 0.505 L?
3.6 103 L
5.14 atm
_ _ _
1000 g
1 mol
22.4 L
4.5 kg 3.6 103 L
28.00 g
1 kg
1 mol
25. Challenge A flexible plastic container
contains 0.860 g of helium gas in a volume
of 19.2 L. If 0.205 g of helium is removed at
constant pressure and temperature, what will be
the new volume?
14.6 L
0.860 g 0.205 g 0.655 g He remaining
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Set up the problem as a ratio.
19.2 L
V
_
_
0.655 g
T 20.0°C 273 293 K
Latm
(0.108 mol)(0.0821 _
)(293 K)
molK
nRT
_
____
P
V
5.14 atm
0.505 L
29. If the pressure exerted by a gas at 25°C in a
volume of 0.044 L is 3.81 atm, how many
moles of gas are present?
6.9 103 mol
n
(3.81 atm)(0.44 L)
PV
_
___
RT
Latm
(0.0821_)(298 K)
mol·K
6.9 103 mol
0.860 g
Solve for V.
(19.2 L)(0.655 g)
V __ 14.6 L
0.860 g
26. Determine the Celsius temperature of 2.49 mol
30. Challenge An ideal gas has a volume of
3.0 L. If the number of moles of gas and the
temperature are doubled while the pressure
remains constant, what is the new volume?
of a gas contained in a 1.00-L vessel at a
pressure of 143 kPa.
12 L
266°C
nT
_P _
Because P and R are constants, they can
143 kPa T
1.00 atm
_
101.3 kPa
1.41 atm
(1.41 atm)(1.00 L)
PV
_
___ 6.90 K
nR
Latm
(2.49 mol)(0.0821 _
)
molK
6.90 K 273 266°C
PV nRT
R
V
be removed from the equation.
n T
n T
_
_ where n
1 1
2 2
V1
V2
2
2n1 and T2 2T1
n T
2n 2T
_
_
1 1
1
V1
V2
1
Multiply both sides by
(2)(2)
_1 _
V1
1
1
_
and _ .
n
1
T1
V2
V2 4V1
V2 4(3.0 L) 12 L
Solutions Manual
Chemistry: Matter and Change • Chapter 13
257
13
Problem-Solving Strategy
SOLUTIONS MANUAL
36. Calculate A 2.00-L flask is filled with
propane gas (C3H8) at a pressure of 1.00 atm
and a temperature of −15.0C. What is the
mass of the propane in the flask?
page 458
Apply the Strategy
Derive Boyle’s law, Gay-Lussac’s law, and the
combined gas law based on the example above.
4.16 g
T 15°C 273 258 K
Students’ work should use the strategy to show the
derivation from the ideal gas law to Boyle’s law
(P1V1 P2V2), Gay-Lussac’s law (P1/T1 P2/T2), and
the combined gas law (P1V1/T1 P2V2/T2).
n
molK
molar mass (3 12.01 g/mol) (8 1.008 g/mol) 44.09 g/mol
Section 13.2 Assessment
mass n M (0.0944 mol)(44.09 g/mol)
4.16 g
page 459
31. Explain why Avogadro’s principle holds true
for gases that have small particles and for gases
that have large particles.
(1.00 atm)(2.00 L)
PV
_
___ 0.0944 mol
RT
Latm
(0.0821 _
)(258 K)
37. Make and Use Graphs For every 6C drop
in temperature, the air pressure in a car’s tires
goes down by about 1 psi (14.7 psi 1.00 atm).
Make a graph illustrating the change in tire
pressure from 20C to 20C (assume 30.0 psi
at 20C).
The size of any gas particle is so small compared
to the volume of the gas, it is assumed that no
particle has any volume of its own.
32. State the equation for the ideal gas law.
Temperature vs. Pressure
33. Analyze how the ideal gas law applies to real
gases using the kinetic-molecular theory.
A real gas behaves most like an ideal gas under
conditions that increase the distance and reduce
the attractions among gas particles. The best
conditions for that are high temperature and low
pressure.
34. Predict the conditions under which a real gas
might deviate from ideal behavior.
A real gas might deviate from ideal behavior
under conditions that decrease the distance and
increase the attractions among gas particles, such
as low temperature and high pressure.
35. List common units for each variable in the ideal
gas law.
P : atm, mm Hg, torr, kPa; V: L, mL; T: K; n: mol
Pressure (psi)
PV nRT
32
30
28
26
24
22
20
-20 -18-16-14-12-10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20
Temperature (°C)
Graph should show air pressure vs. temperature;
the resulting plot will be a straight line showing a
direct relationship between the variables.
Section 13.3 Gas Stoichiometry
pages 460–464
Practice Problems
pages 461–463
38. How many liters of propane gas (C3H8) will
undergo complete combustion with 34.0 L of
oxygen gas?
6.80 L C3H8
C3H8(g) 5O2(g) 0 3CO2(g) 4H2O(g)
34.0 L O2 258
Chemistry: Matter and Change • Chapter 13
1LC H
_
6.80 L C H
3 8
5 L O2
3 8
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CHAPTER
13
CHAPTER
SOLUTIONS MANUAL
39. Determine the volume of hydrogen gas needed
to react completely with 5.00 L of oxygen gas
to form water.
10.0 L H2
2H2(g) O2(g) 0 2H2O(g)
2LH
_
10.0 L H
2
1 L O2
CaCO3 0 CaO CO2
40. What volume of oxygen is needed to
completely combust 2.36 L of methane
gas (CH4)?
2.38 kg 1 mol CaCO
1000 g
_
__ 3
100.09 g
1 kg
1 mol CO
22.4 L
__
_ 533 L CO
2
4.72 L O2
1 mol CaCO3
CH4(g) 2O2(g) 0 CO2(g) 2H2O(g)
2.36 L CH4 _ 4.72 L O
oxygen to form iron(III) oxide.
2
1 L CH4
2
1 mol
44. When iron rusts, it undergoes a reaction with
2 L O2
41. Challenge Nitrogen and oxygen gases react
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
heated, it decomposes to form solid calcium
oxide (CaO) and carbon dioxide gas (CO2).
How many liters of carbon dioxide will
be produced at STP if 2.38 kg of calcium
carbonate reacts completely?
533 L CO2
2
5.00 L O2 43. When solid calcium carbonate (CaCO3) is
4Fe(s) 3O2(g) 0 2Fe2O3(s)
to form dinitrogen monoxide gas (N2O). What
volume of O2 is needed to produce 34 L of
N2O?
Calculate the volume of oxygen gas at STP that
is required to completely react with 52.0 g of
iron.
17 L O2
15.6 L O2
N2 O2 N2O
52.0 g Fe 2N2 O2 2N2O
15.6 L O2
34 L N2O 1LO
_
17 L O
3 mol O
1 mol Fe
22.4 L
_
__
2
55.85 g Fe
4 mol Fe
1 mol
2
2
2 L N2O
42. Ammonium nitrate is a common ingredient in
chemical fertilizers. Use the reaction shown to
calculate the mass of solid ammonium nitrate
that must be used to obtain 0.100 L of dinitrogen monoxide gas at STP.
NH4NO3(s) 0 N2O(g) 2H2O(g)
0.357 g NH4NO3
0.100 L N2O 1 mol
_
0.00446 mol N O
2
22.4 L
0.00446 mol N2O 1 mol NH NO
__
4
3
1 mol N2O
0.00446 mol NH4NO3
0.00446 mol NH4NO3 80.03 g/mol
0.357 g NH4NO3
Solutions Manual
Chemistry: Matter and Change • Chapter 13
259
13
SOLUTIONS MANUAL
45. Challenge An excess of acetic acid is added
to 28 g of sodium bicarbonate at 25°C and
1 atm pressure. During the reaction, the gas
cools to 20°C. What volume of carbon dioxide
will be produced? The balanced equation for
the reaction is shown below.
NaHCO3(aq) CH3COOH(aq) 0
indirectly proportional to the number of moles
of a gas at constant temperature and pressure?
Explain.
Directly proportional; as the amount of gas
increases, so does volume.
48. Calculate One mole of a gas occupies a
volume of 22.4 L at STP. Calculate the temperature and pressure conditions needed to fit
2 mol of a gas into a volume of 22.4 L.
NaCH3COO(aq) CO2(g) H2O(l)
7.9 L CO2
Molecular mass of sodium bicarbonate
83.9 g/mole
28 g NaHCO3 47. Analyze Is the volume of a gas directly or
Student answers may vary. Temperature can be
halved or pressure doubled or a combination of
lowering temperature and increasing pressure.
1 mol NaHCO
__
3
83.9 g
49. Interpret Data Ethene gas (C2H4) reacts with
0.33 mol NaHCO3
For each mole of sodium bicarbonate, one mole
of CO2 is produced, so 0.33 mol NaHCO3 will
produce 0.33 mol CO2.
oxygen to form carbon dioxide and water. Write
a balanced equation for this reaction, then find
the mole ratios of substances on each side of
the equation.
For an ideal gas, molar volume is 22.4 L at 273 K
and 1 atm.
C2H4(g) 3O2(g) 0 2CO2 2H2O
1:3
T 20°C 273 293 K
0.33 mol CO2 293 K
22.4 L
_
_ 7.9 L of CO
273 K
1 mol
2
2:2
Chapter 13 Assessment
pages 468–471
Section 13.3 Assessment
page 464
46. Explain When fluorine gas combines with
water vapor, the following reaction occurs.
2F2(g) 2H2O(g) 0 O2(g) 4HF(g)
If the reaction starts with 2 L of fluorine gas,
how many liters of water vapor react with the
fluorine, and how many liters of oxygen and
hydrogen fluoride are produced?
2 L H2O, 1 L O2, and 4 L HF
260
2 L F2 2LH O
_
2LH O
2 L F2 1LO
_
1LO
2 L F2 4 L HF
_
4 L HF
2
2
2 L F2
2
2 L F2
2
2 L F2
Chemistry: Matter and Change • Chapter 13
Section 13.1
Mastering Concepts
50. State Boyle’s law, Charles’s law, Gay-Lussac’s
law, and the combined gas law in words and
equations.
Boyle’s law: the volume of a given amount
of gas held at a constant temperature varies
inversely with pressure, P1V1 P2V2; Charles’s
law: the volume of a given mass of gas is directly
proportional to its kelvin temperature at constant
pressure, V1/T1 V2/T2; Gay-Lussac’s law: the
pressure of a given mass of gas varies directly
with the kelvin temperature when the volume
remains constant, P1/T1 P2/T2; combined gas
law: states the relationship among pressure,
volume, and temperature of a fixed amount of
gas, P1V1/T1 P2V2/T2
Solutions Manual
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CHAPTER
13
CHAPTER
SOLUTIONS MANUAL
51. If two variables are inversely proportional, what
happens to the value of one as the value of the
other increases?
One variable always decreases as the other
increases.
52. If two variables are directly proportional, what
happens to the value of one as the value of the
other increases?
One variable always increases as the other
increases.
56. Weather Balloons A weather balloon is
filled with helium that occupies a volume of
5.00 × 10 4 L at 0.995 atm and 32.0°C. After
it is released, it rises to a location where the
pressure is 0.720 atm and the temperature is
12.0°C. What is the volume of the balloon at
the new location?
5.91 10 4 L
T1 32.0°C 273 295 K
T2 12°C 273 261 K
53. List the standard conditions for gas
V2 P V T
(0.995 atm)(5.00 10 L)(261 K)
_
___
measurements.
T 0.00°C (273 K) and P 1.00 atm
4
1 1 2
T1P2
5.91 10 4 L
(305 K)(0.720 atm)
57. Use Boyle’s, Charles’s, or Gay-Lussac’s law
54. Identify the units most commonly used for P,
V, and T.
atm for pressure, kelvin for temperature, and L
for volume
to calculate the missing value in each of the
following.
a. V1 2.0 L, P1 0.82 atm,
V2 1.0 L, P2 ?
1.6 atm
Mastering Problems
Temperature and Volume Data
800
700
1 1
V2
(1.0 L)
V2 400 mL, T2 298 K
200 K
500
400
T1 (200 K, 400 mL)
300
200
0
50
100
150
200
250
T V
(298 K)(250 mL)
_
__ 186 K 200 K
2 1
V2
(400 mL)
c. V1 0.55 L, P1 740 mm Hg,
(100 K, 200 mL)
100
0
P V
(0.82 atm)(2.0 L)
_
__ 1.6 atm
b. V1 250 mL, T1 ?,
(300 K, 600 mL)
600
Volume (mL)
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
P2 V2 0.80 L, P2 ?
300
350
400
Temperature (K)
55. Use Charles’s law to determine the accuracy of
the data plotted in Figure 13.13.
510 mm Hg
P2 P V
(740 mm Hg)(0.55 L)
_
__
1 1
V2
510 mm Hg
(0.80 L)
Charles’s law states that the volume of a
given mass of gas is directly proportional to
temperature. The graphed data follow this law
because doubling the temperature doubles the
volume, so the data are accurate.
Solutions Manual
Chemistry: Matter and Change • Chapter 13
261
13
SOLUTIONS MANUAL
Section 13.2
58. Hot-Air Balloons A sample of air
occupies 2.50 L at a temperature of 22.0°C.
What volume will this sample occupy inside
a hot-air balloon at a temperature of 43.0°C?
Assume that the pressure inside the balloon
remains constant.
2.68 L
T1 22.0°C 273 295 K
V2 The ideal gas law describes the physical behavior
of an ideal gas in terms of the pressure, volume,
temperature, and number of moles of gas
present.
_ __
T1
(2.50 L)(316 K)
2.68 L
(295 K)
59. What is the pressure of a fixed volume of
hydrogen gas at 30.0°C if it has a pressure of
1.11 atm at 15.0°C?
1.17 atm
at STP? What volume does 2 mol occupy at
STP?
64. Define the term ideal gas, and explain why there
T2 30.0°C 273 303 K
P T
(1.11 atm)(303 K)
_ __ 1.17 atm
1 2
T1
63. What volume is occupied by one mol of a gas
22.4 L; 44.8 L
T1 15.0°C 273 288 K
P2
At a fixed temperature and pressure, equal
volumes of any ideal gas contain equal numbers
of particles.
62. State the ideal gas law.
T2 43.0°C 273 316 K
V1T2
Mastering Concepts
61. State Avogadro’s principle.
(288 K)
N2
N2
are no true ideal gases in nature.
An ideal gas is one whose particles take up no
space and have no intermolecular attractive
forces, and it follows the gas laws under all
conditions of temperature and pressure. No
gas is truly ideal because all gas particles have
some volume and are subject to intermolecular
interactions.
65. List two conditions under which a gas is least
likely to behave ideally.
high pressure and low temperature
66. What units must be used to express the temper-
V1 = 500 mL
P1 = 108 KPa
T1 = 10.0°C
V2 = 750 mL
T2 = 21.0°C
60. A sample of nitrogen gas is transferred to a
ature in the equation for the ideal gas law?
Explain.
Kelvin units; V is not directly proportional to
Celsius temperature.
large flask, as shown in Figure 13.14. What is
the pressure of nitrogen in the second flask?
74.8 kPa
T1 10.0°C 273 283 K
T2 21.0°C 273 294 K
P2 P V T
(108 kPa)(500.0 mL)(294 K)
_
___
1 1 2
T1V2
74.8 kPa
262
(283 K)(750.0 mL)
Chemistry: Matter and Change • Chapter 13
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
CHAPTER
CHAPTER
13
SOLUTIONS MANUAL
Mastering Problems
67. Home Fuel Propane (C3H8) is a gas
commonly used as a home fuel for cooking and
heating.
a. Calculate the volume that 0.540 mol of
propane occupies at STP.
12.1 L
22.4 L
0.540 mol _ 12.1 L
1 mol
b. Think about the size of this volume and the
amount of propane that it contains. Why do
you think propane is usually liquefied before
it is transported?
Propane occupies a much smaller volume
when liquefied.
68. Careers in Chemistry A physical chemist
measured the lowest pressure achieved in a
laboratory—about 1.0 1015 mm Hg. How
many molecules of gas are present in a 1.00-L
sample at that pressure if the sample’s temperature is 22.0ºC?
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
3.3 10 4 molecules
T 22.0°C 273 295 K
_ ___
_
(1.0 1015 mm Hg)(1.00 L)
PV
n
RT
Lmm Hg
(62.4
)(295 K)
molK
5.4 10 20 mol
___
6.02 10 23 molecules
5.4 1020 mol 1 mol
3.3 10 4 molecules
70. Perfumes Geraniol is a compound found in
rose oil that is used in perfumes. What is the
molar mass of geraniol if its vapor has a density
of 0.480 g/L at a temperature of 260.0°C and a
pressure of 0.140 atm?
1.50 10 2 g/mol
Assume 1 mol of geraniol.
T 260.0°C 273 533 K
Latm
(1 mol)(0.0821_
)(533 K)
molK
nRT
_
___
V
313 L
P
0.140 atm
mass density volume (0.480 g/L)(313 L)
1.50 10 2 g in 1 mole
71. Find the volume that 42 g of carbon monoxide
gas occupies at STP.
34 L
n 42 g CO 1 mol CO
__
1.5 mol CO
V 1.5 mol 22.4 L
_
34 L
28.01 g CO
1 mol
72. Determine the density of chlorine gas at 22.0°C
and 1.00 atm.
2.93 g/L
Molar mass Cl2 70.90 g/mol
T 22.0°C 273 295 K
_ ___
(70.90 g/mol)(1.00 atm)
D MP (0.0821 L atm/mol · K)(295 K)
RT
2.93 g/L
69. Calculate the number of moles of O2 gas held
in a sealed, 2.00-L tank at 3.50 atm and 25.0°C.
How many moles would be in the tank if the
temperature was raised to 49.0°C and the pressure remained constant?
0.286 mol; 0.265 mol
T 25.0°C 273 298 K
n
(3.50 atm)(2.00 L)
PV
_
___ 0.286 mol
RT
Latm
(0.0821 _
)(298 K)
molK
T 49.0°C 273 322 K
n
(3.50 atm)(2.00 L)
PV
_
___ 0.265 mol
RT
Latm
(0.0821 _
)(322 K)
molK
Solutions Manual
Chemistry: Matter and Change • Chapter 13
263
13
CHAPTER
SOLUTIONS MANUAL
P = 1.08 atm
T = 15.0°C
0.0
Mass of N2
0.38 kg
Atm
5.0
Mass of C3H8
0.52 kg
3.0
4.0
Nitrogen
N2
1.0
2.0
Propane
C3H8
73. Which of the gases in Figure 13.15 occupies
75. A 2.00-L flask is filled with ethane gas (C2H6)
the greatest volume at STP? Explain
your answer.
The N2 occupies the greatest volume at STP. The
N2 occupies 310 L, while the C3H8 occupies only
260 L.
1000 g
1 mol
0.52 kg C3H8 11.8 mol C3H8
44.1 g
1 kg
_ _
22.4 L
_
260 L C H
0.38 kg N2
28.0 g
2
22.4 L
_
310 L N
2
1 mol
74. If the containers in Figure 13.15 each hold
4.00 L, what is the pressure inside each?
Assume ideal behavior.
propane: 66.1 atm; nitrogen: 76.2 atm
(1.08 atm)(2.00 L)
PV
_
___ 0.0914 mol
RT
Latm
(0.0821 _
)(288 K)
molar mass (2 12.01 g/mol) (6 1.008 g/mol) 30.07 g/mol
mass n M (0.0914 mol)(30.07 g/mol)
2.75 g
76. What is the density of a sample of nitrogen
gas (N2) that exerts a pressure of 5.30 atm in a
3.50-L container at 125°C?
4.55 g/L
g
_
)(5.30 atm)
mol
MP
D _ ___ 4.55 g/L
RT
Latm
(0.0821 _ )(398 K)
(28.0
PV nRT
propane:
Latm
(11.8 mol C H )(0.0821 _
)(273 K)
molK
nRT
_
____
P
3 8
V
66.1 atm
4.00 L
nitrogen:
Latm
_
)(273 K)
molK
nRT
_
____
P
(13.6 mol N2)(0.0821
V
76.2 atm
n
molK
1000 g
1 mol
_ _ 13.6 mol N
13.6 mol T 15°C 273 288 K
3 8
1 mol
1 kg
2.75 g
molK
77. How many moles of helium gas (He) would be
required to fill a 22-L container at a temperature of 35°C and a pressure of 3.1 atm?
2.7 mol
T 35°C 273 308 K
4.00 L
n
(3.1 atm)(22 L)
PV
_
___ 2.7 mol
RT
Latm
)(308 K)
(0.0821 _
molK
264
Chemistry: Matter and Change • Chapter 13
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
11.8 mol from a small cylinder, as shown in Figure 13.16.
What is the mass of the ethane in the flask?
CHAPTER
13
78. Before a reaction, two gases share a container at
a temperature of 200 K. After the reaction, the
product is in the same container at a temperature of 400 K. If both V and P are constant,
what must be true of n?
With a constant volume and pressure and
doubling of the temperature, the number of
moles would be half the initial number of moles.
Section 13.3
Mastering Concepts
79. Why must an equation be balanced before using
it to determine the volumes of gases involved in
a reaction?
Equation coefficients represent ratios among gas
volumes in the reaction.
80. It is not necessary to consider temperature and
pressure when using a balanced equation to
determine relative gas volume. Why?
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Temperature and pressure are the same for each
gas involved in the reaction. These conditions
affect each gas in the same way.
SOLUTIONS MANUAL
Mastering Problems
84. Ammonia Production Ammonia is often
formed by reacting nitrogen and hydrogen
gases. How many liters of ammonia gas can be
formed from 13.7 L of hydrogen gas at 93.0°C
and a pressure of 40.0 kPa?
9.13 L NH3
N2 3H2 0 2NH3
13.7 L H2 balanced equation, at least one mass or volume
value for a reactant or product, and P and T
conditions under which gas volumes have been
measured
82. Explain why the coefficients in a balanced
chemical equation represent not only molar
amounts but also relative volumes for gases.
Avogadro’s principle states that equal volumes
of gases at the same temperature and pressure
contain equal numbers of particles (or an equal
number of moles). Therefore, the coefficients also
represent the relative volumes of the gases.
3
3
3 L H2
85. A 6.5-L sample of hydrogen sulfide is treated
with a catalyst to promote the reaction shown
below.
2H2S(g) O2(g) 0 2H2O(g) 2S(s)
If the H2S reacts completely at 2.0 atm and
290 K, how much water vapor, in grams, is
produced?
9.7 g
Determine volume ratios from the balanced
chemical equation:
81. What information do you need to solve a
volume-mass problem that involves gases?
2 L NH
_
9.13 L NH
6.5 L H2S
n
n
(
2LH O
_
2
2 L H2S
)
2 volumes H S
__
2
2 volumes H2O
6.5 L H2O
PV
_
RT
(2.0 atm)(6.5 L H O)
___
0.54 mol
Latm
)(290 K)
(0.0821 _
2
molK
molar mass (2 1.008 g/mol)
(1 15.999 g/mol) 18.015 g/mol
mass n M (0.54 mol)(18.015 g/mol) 9.7 g
83. Do the coefficients in a balanced chemical
equation represent volume ratios for solids and
liquids? Explain.
No, this relationship only applies to gases that
behave like ideal gases.
Solutions Manual
Chemistry: Matter and Change • Chapter 13
265
13
SOLUTIONS MANUAL
89. When heated, solid potassium chlorate (KClO3)
86. To produce 15.4 L of nitrogen dioxide at 310 K
and 2.0 atm, how many liters of nitrogen gas and
oxygen gas are required?
N2 gas: 7.7 L; O2 gas: 15.4 L
Write a balanced chemical equation:
N2 2O2 0 2NO2
decomposes to form solid potassium chloride
and oxygen gas. If 20.8 g of potassium chlorate
decomposes, how many liters of oxygen gas
will form at STP?
5.70 L
2KClO3 0 2KCl 3O2
The molar relationship between O2 and NO2 is
1:1 based on the balanced chemical equation.
Therefore, the volume of O2 gas is 15.4 L. The
molar relationship between N2 and NO2 is 1:2.
molar mass KClO3 39.10 g/mol 35.45 g/mol
(3 16.00 g/mol) 122.55 g/mol
nKClO 20.8 g KClO3 1LN
(15.4 L NO2) _ 7.7 L N2
3
2
2 L NO2
0.170 mol KClO3
87. Use the reaction shown below to answer these
nO 0.170 mol KClO3 questions.
2
2CO(g) + 2NO(g) 0 N2(g) + 2CO2(g)
a. What is the volume ratio of carbon monoxide
to carbon dioxide in the balanced equation?
1:1
at STP, what volume of N2 gas will be
produced?
2
3 mol O
__
2
2 mol KClO3
22.4 L
_
5.70 L O
2
1 mol
90. Acetylene The gas acetylene, often used for
2C2H2(g) 5O2(g) 0 2H2O(g) 4CO2(g)
If you have a 10.0-L tank of acetylene at
25.0°C and 1.00 atm pressure, how many moles
of CO2 will be produced if you burn all the
acetylene in the tank?
17.1 L
1 mol CO
__
1.52 mol CO
28.01 g CO
nN 1.52 mol CO V 0.255 mol 3
122.55 g KClO3
welding, burns according to the following
equation.
b. If 42.7 g of CO is reacted completely
nCO 42.7 g CO 0.255 mol O2
1 mol KClO
__
1 mol N
_
0.762 mol N
2
2
2 mol CO
0.817 mol
(10.0 L C2H2) VN (0.762 mol) (22.4 L/mol) 17.1 L
2
4 volumes CO
__
20.0 L CO
2
2 volumes C2H2
2
T 25°C 273 298 K
88. When 3.00 L of propane gas is completely
combusted to form water vapor and carbon
dioxide at 350°C and 0.990 atm, what mass of
water vapor results?
n
(1.00 atm)(20.0 L)
PV
_
___ 0.817 mol CO
Latm
RT
(0.0821 _
)(298 K)
2
molK
4.2 g
2C3H8 10O2 0 6CO2 8H2O
3.00 L C3H8 8LH O
_
12.0 L H O
2
2 L C3H8
2
T 350°C 273 623 K
(0.990 atm)(12.0 L)
PV
_
___ 0.232 mol H O
RT
Latm
)(623 K)
(0.0821 _
molK
18.02 g H O
mass 0.232 mol H O __
n
2
2
2
4.2 g H2O
266
1 mol H2O
Chemistry: Matter and Change • Chapter 13
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
CHAPTER
13
CHAPTER
SOLUTIONS MANUAL
Mixed Review
91. Gaseous methane (CH4) undergoes complete
combustion by reacting with oxygen gas to
form carbon dioxide and water vapor.
a. Write a balanced equation for this reaction.
CH4(g) 2O2(g) 0 CO2(g) 2H2O(g)
94. Determine how many liters 8.80 g of carbon
dioxide gas would occupy at:
n 8.80 g CO2 0.200 mol CO2
a. STP
4.48 L
b. What is the volume ratio of methane to
water in this reaction?
V 0.200 mol 1:2
1 mol CO
__
2
44.01 g CO2
22.4 L
_
4.48 L
1 mol
b. 160°C and 3.00 atm
2.37 L
T 160°C 273 433 K
125°C
Atm
5.0
0.0
4.0
7.0 L
V
3.0
1.0
2.0
92. Calculate the amount of water vapor, in grams,
contained in the vessel shown in Figure 13.17.
3.9 g
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
T 125°C 273 398 K
g
(18.015 _)(1.0 atm)(7.0 L)
MPV
_
mol
___
m
3.9 g
RT
Latm
(0.0821_
)(398 K)
molK
93. Television Determine the pressure inside a
television picture tube with a volume of 3.50 L
that contains 2.00 105 g of nitrogen gas at
22.0°C.
4.94 106 atm
n 2.00 105
g N2
1 mol N
__
P
L atm
)(433 K)
(0.200 mol)(0.0821 molK
3.00 atm
2.37 L
_
____
c. 288 K and 118 kPa
4.06 L
LkPa
(0.200 mol)(8.314 _
)(288 K)
molK
nRT
_
____
V
P
4.06 L
28.02 g N2
118 kPa
95. Oxygen Consumption If 5.00 L of hydrogen
gas, measured at a temperature of 20.0ºC and
a pressure of 80.1 kPa, is burned in excess
oxygen to form water, what mass of oxygen
will be consumed? Assume temperature and
pressure remain constant.
2.63 g
2H2(g) O2(g) 0 2H2O(g)
2
7.14 107 mol
VO 5.00 L H2 2
1LO
_
2.50 L O
2
Latm
)(295 K)
(7.14 10 mol)(0.0821 _
molK
nRT
_
____
P
7
3.50 L
(80.1 kPa)(2.50 L)
PV
_
__ 0.0822 mol O
RT
LkPa
(8.314 _ )(293 K)
molK
32.00 g O
mass 0.0822 mol O __ 2.63 g O
n
2
2
2
Solutions Manual
2
2 L H2
T 20.0°C 273 293 K
T 22.0°C 273 295 K
V
4.94 106 atm
nRT
_
1 mol O2
Chemistry: Matter and Change • Chapter 13
2
267
13
SOLUTIONS MANUAL
98. Respiration A human breathes about 0.50 L
96. A fixed amount of oxygen gas is held in a
1.00-L tank at a pressure of 3.50 atm. The
tank is connected to an empty 2.00-L tank by
a tube with a valve. After this valve has been
opened and the oxygen is allowed to flow freely
between the two tanks at a constant temperature, what is the final pressure in the system?
1.17 atm
P2
1.2 L
_ ___
_
(760 mm Hg)(0.50 L)
n PV 0.022 mol
RT
Lmm Hg
) (273 K)
(62.4
molK
T 60°C 273 213 K
(3.50 atm)(1.00 L)
_ __ 1.17 atm
P1V1
V2
of air during a normal breath. Assume the
conditions are at STP.
a. What is the volume of one breath on a cold
day atop Mt. Everest? Assume 60ºC and
253 mm Hg pressure.
3.00 L
97. If 2.33 L of propane at 24°C and 67.2 kPa is
completely burned in excess oxygen, how many
moles of carbon dioxide will be produced?
Lmm Hg
(0.022 mol)(62.4_)(213 K)
molK
nRT
_
____
V
P
1.2 L
0.19 mol
C3H8 5O2 0 3CO2 4H2O
2.33 L C3H8 b. Air normally contains about 21% oxygen.
_ 6.99 L CO
3 L CO2
1 L C3H8
2
T 24°C 273 297 K
n
253 mm Hg
(67.2 kPa)(6.99 L)
PV
_
__ 0.190 mol CO
RT
LkPa
(8.314 _
)(297 K)
2
molK
If the O2 content is about 14% atop Mt.
Everest, what volume of air does a person
need to breathe to supply the body with the
same amount of oxygen?
0.75 L
21%
_
100 1.5
14%
0.50 L 1.5 0.75 L
Think Critically
99. Apply An oversized helium balloon in a
floral shop must have a volume of at least
3.8 L to rise. When 0.1 mol is added to the
empty balloon, its volume is 2.8 L. How many
grams of He must be added to make it rise?
Assume constant T and P.
0.56 g
n
V
_
_
n
1
1
2
V2
n2 n V
(0.1 mol)(3.8 L)
_
__ 0.14 mol
1 2
V1
0.14 mol 4.003
268
Chemistry: Matter and Change • Chapter 13
2.8 L
g
_
mol
0.56 g
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
CHAPTER
CHAPTER
13
SOLUTIONS MANUAL
100. Calculate A toy manufacturer uses tetrafluo-
roethane (C2H2F4) at high temperatures to fill
plastic molds for toys.
a. What is the density (in g/L) of C2H2F4 at
STP?
4.55 g/L
molar mass (2 12.011 g/mol) (2 1.008 g/mol) (4 18.998 g/mol)
102 g/mol
g
(102 _) (1.00 atm)
mol
MP
D _ ___ 4.55 g/L
Latm
RT
(0.0821_
) (273 K)
molK
b. Find the molecules per liter of C2H2F4 at
220°C and 1.0 atm.
1.51 10 22 molecules per liter
n
(1.0 atm) (1.0 L)
PV
_
___
RT
Latm
(0.0821 _
) (493 K)
n 0.025 mol
molK
1 L of C2H2F4 contains 0.025 mol
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
1 mole 6.023 1023 molecules
0.025 mol 6.023 10 molecules
___
23
1 mol
1.51 10 22 molecules
101. Analyze A solid brick of dry ice (CO2)
weighs 0.75 kg. Once the brick has fully
sublimated into CO2 gas, what would its
volume be at STP?
381 L
0.75 kg 750 g
750 g
_
17.0 moles
g
44 _
mol
22.4 L
_
17.0 mol 381 L
1 mol
Solutions Manual
102. Apply Calculate the pressure of 4.67 10 22
molecules of CO gas mixed with 2.87 10 24
molecules of N2 gas in a 6.00-L container at
34.8°C.
20.4 atm
nCO 4.67 10 22 molecules
1 mol
0.0776 mol CO
6.02 10 23 molecules
___
nN 2.87 10 24 molecules
2
1 mol
___ 4.77 mol N
2
6.02 10 23 molecules
ntotal 0.0776 mol CO 4.77 mol N2 4.85 mol
T 34.8°C 273 307.8 K
Latm
(4.85 mol) (0.0821 _
) (307.8 K)
molK
nRT
_
____
P
V
20.4 atm
6.00 L
103. Apply When nitroglycerin (C3H5N3O9)
explodes, it decomposes into the following
gases: CO2, N2, NO, and H2O. If 239 g of
nitroglycerin explodes, what volume will the
mixture of gaseous products occupy at
1.00 atm pressure and 2678°C?
1850 L
molar mass C3H5N3O9 (3 12.01) (5 1.008)
(3 14.01) (9 16.00) 227.10 g/mol
n 239 g C3H5N3O9 1.05 mol C3H5N3O9
1 mol C H N O
__
3 5 3
9
227.10 g C3H5N3O9
4C3H5N3O9(s) 0 12CO2(g) 5N2(g) 2NO(g) 10H2O(g)
29 mol gas products
1.05 mol C3H5N3O9 4 mol C3H5N3O9
7.61 mol gas products
__
V
nRT
_
P
L atm
) (2951 K)
(7.61 mol) (0.0821 molK
1850 L
1.00 atm
_
____
Chemistry: Matter and Change • Chapter 13
269
13
SOLUTIONS MANUAL
104. Make and Use Graphs The data in
105. Apply What is the numerical value of the
Table 13.3 show the volume of hydrogen gas
collected at several different temperatures.
Illustrate these data with a graph. Use the
graph to complete the table. Determine the
temperature at which the volume will reach
a value of 0 mL. What is this temperature
called?
Volume of H2 Collected
Trial
T(°C)
V(mL)
300
48
2
175
37
3
110
32
4
0
22
5
100
15
6
150
11
8.314 106
R
cm Pa
_
3
molK
1000 cm
1000 Pa
8.314 LkPa _
__
_
3
molk
1L
1 kPa
cm Pa
_
3
molK
gas law calculate a pressure that is higher
or lower than the actual pressure exerted by
a sample of gas? How will the calculated
pressure compare to the actual pressure at low
temperatures? Explain your answers.
At high pressures and low temperatures, the
ideal gas law will calculate a pressure that
is higher than the gas actually exerts. Under
these conditions, the effects of intermolecular
forces become more important. Attractions
between particles will lower the force of the
collisions with the container wall, resulting in an
actual pressure that is lower than the pressure
calculated by the ideal gas law.
40
Volume (mL)
molK
106. Infer At very high pressures, will the ideal
Volume vs. Temperature
30
Challenge Problem
107. Baking A baker uses baking soda as the
leavening agent for his pumpkin-bread recipe.
The baking soda decomposes according to two
possible reactions.
20
10
0
300 200 100
0
100
Temperature (°C)
3
8.314 10 6
1
50
ideal gas constant (R) in
cm Pa ?
_
200
300
Extrapolating the graph to a volume of 0 mL
intersects the temperature axis at approximately
273°C, the temperature called absolute zero.
2NaHCO3(s) 0 Na2CO3(s) H2O(l) CO2(g)
NaHCO3(s) H(aq) 0 H2O(l) CO2(g)
Na(aq)
Calculate the volume of CO2 that forms per
gram of NaHCO3 by each reaction process.
Assume the reactions take place at 210°C and
0.985 atm.
2NaHCO3(s) 0 Na2CO3(s) H2O(l) CO2(g)
0.24 L per gram
NaHCO3(s) H (aq) 0 H2O(l) CO2(g)
Na(aq) 0.48 L per gram
(1) 2NaHCO3(s) 0 Na2CO3(s) H2O(l) CO2(g)
270
Chemistry: Matter and Change • Chapter 13
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CHAPTER
13
CHAPTER
SOLUTIONS MANUAL
Molar ratio between NaHCO3 and CO2: 2:1
109. Write the electron configuration for each atom.
Latm
(1.0 mol) (0.0821 _
) (483 K)
mol K
nRT
_
___
V
P
(Chapter 5)
a. iodine
0.985 atm
[Kr] 4d10 5s2 5p5
V 40.2 L of CO2
b. boron
2 mol of NaHCO3 produces 40.2 L of CO2
[He] 2s2 2p1
2 mol 84.2 g/mole 168 g of NaHCO3
168 g of NaHCO3 produces 40.2 L of CO2
c. chromium
40.2 L/168 g 0.24 L/g
(2) NaHCO3(s) Na(aq)
H(aq)
[Ar] 3d5 4s1
→ H2O(l) CO2(g) d.
[Ar] 3d10 4s2 4p6
Molar ratio between NaHCO3 and CO2: 1:1
L atm
(1.0 mol) (0.0821 _) (483 K)
mol K
nRT ___
_
V
e. calcium
V 40.2 L of CO2
f. cadmium
P
[Ar] 4s2
0.985 atm
1 mol of NaHCO3 produces 40.2 L of CO2
[Kr] 4d10 5s2
84 g of NaHCO3 produces 40.2 L of CO2
110. For each element, tell how many electrons are
40.2 L/84 g 0.48 L/g
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
krypton
Cumulative Review
108. Convert each mass measurement to its equivalent
in kilograms. (Chapter 2)
a. 247 g
1 kg
_
0.247 kg
103 g
2, 8, 5; P
d. B
10 4
53 mg b. Sr
c. P
b. 53 mg
5.3 2, 8, 18, 8; Kr
2, 8, 18, 8, 2; Sr
0.247 kg
247 g in each energy level and write the electron dot
structure. (Chapter 5)
a. Kr
kg
2, 3; B
1g
1 kg
_
_ 5.3 10
5
103 mg
e. Br
kg
103 g
2, 8, 18, 7; Br
c. 7.23 mg
f. Se
7.23 103 kg
7.23 mg 1 kg
1g
_
_ 7.23 10
6
103 mg
103 g
2, 8, 18, 6; Se
kg
d. 975 mg
9.75 104 kg
975 mg Solutions Manual
1 kg
1g
_
_ 9.75 10
4
103 mg
103 g
kg
Chemistry: Matter and Change • Chapter 13
271
CHAPTER
13
111. How many atoms of each element are present
in five formula units of calcium permanganate? (Chapter 7)
5 formula units Ca(MnO4)2: 5Ca, 10Mn, 40 O
112. You are given two clear, colorless aqueous
solutions. One solution contains an ionic
compound, and one contains a covalent
compound. How could you determine which
is an ionic solution and which is a covalent
solution? (Chapter 8)
The ionic solution will conduct electricity. The
covalent solution will not conduct electricity.
113. Write a balanced equation for the following
reactions. (Chapter 9)
a. Zinc displaces silver in silver chloride.
SOLUTIONS MANUAL
83.07 g/mol
g
_
mol
n _ 艐 2.00
g
83.07 _
166
mol
molecular formula: C8H6O4
115. The particles of which gas have the highest
average speed? The lowest average speed?
(Chapter 12)
a. carbon monoxide at 90°C
b. nitrogen trifluoride at 30°C
c. methane at 90°C
d. carbon monoxide at 30°C
c, b
Average speed is greater at higher temperature
and lower at greater molar mass
Zn(s) 2AgCl(aq) 0 ZnCl2(aq) 2Ag(s)
form sodium sulfate and water.
2NaOH(aq) H2SO4(aq) 0 Na2SO4(aq)
2H2O(l)
114. Terephthalic acid is an organic compound
used in the formation of polyesters. It contains
57.8% C, 3.64% H, and 38.5% O. The molar
mass is approximately 166 g/mol. What is
the molecular formula of terephthalic acid?
(Chapter 10)
C8H6O4
57.8 g C 1 mol C
_
4.81 mol C
3.64 g H 1 mol H
_
3.60 mol H
12.01 g C
Writing in Chemistry
116. Hot-Air Balloons Many early balloonists
dreamed of completing a trip around the world
in a hot-air balloon, a goal not achieved until
1999. Write about what you imagine a trip in a
balloon would be like, including a description
of how manipulating air temperature would
allow you to control altitude.
Student answers should include a description of
how the difference in density of hot air and cold
air is what allows hot-air balloons to stay aloft,
and how manipulating the rate of heating of air
allows a balloonist to ascend and descend.
1.01 g H
1 mol O
38.5 g O _ 2.41 mol O
16.00 g O
4.81 mol C
__
2.00 mol C
2.41
3.60 mol H
__
1.50 mol H
2.41
2.41 mol O
__
1.00 mol O
2.41
empirical formula: C4H3O2
molar mass C4H3O2 (4 12.01 g/mol)
(3 1.01 g/mol) (2 16.00 g/mol)
272
Additional Assessment
Chemistry: Matter and Change • Chapter 13
117. Scuba Investigate and explain the function of
the regulators on the air tanks used by scuba
divers.
Student answers should include the overall
function of the air tank regulator, a device that
changes air pressure levels and delivers air. The
first stage regulator is the regulator attached to
the scuba tank, and it lowers the tank pressure
to ambient pressure plus a predetermined
pressure (e.g., ambient 140 psi). The second
stage regulator follows the first stage regulator
in line, and it delivers compressed air to the
diver.
Solutions Manual
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
b. Sodium hydroxide and sulfuric acid react to
13
CHAPTER
SOLUTIONS MANUAL
Document-Based Questions
Standardized Test Practice
The Haber Process Ammonia (NH 3) is used in the
production of fertilizer, refrigerants, dyes, and plastics. The Haber process is a method of producing
ammonia through a reaction of molecular nitrogen
and hydrogen. The equation for the reversible
reaction is:
N2(g) 3H2(g) a 2 NH3(g) 92 kJ
pages 472–473
Percent yield of ammonia
350°C
60
400°C
50
450°C
40
30
500°C
20
550°C
10
0
0
100
200
300
400
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Pressure (atm)
118. Explain how the percent yield of ammonia is
affected by pressure and temperature.
Ammonia yield is increased by very high
pressures. Yield decreases at very high
temperatures.
119. The Haber process is typically run at 200 atm
and 450°C, a combination proven to yield a
substantial amount of ammonia in a short time.
a. What effect would running the reaction
above 200 atm have on the temperature of
the containment vessel?
Gas A
1000
Gas B
800
600
Gas C
400
Gas D
200
The Haber Process
70
Pressures of Four Gases
at Different Temperatures
1200
Pressure (kPa)
Figure 13.18 shows the effect of temperature and
pressure on the amount of ammonia produced by the
Haber process.
Use the graph below to answer Questions 1 and 2.
0
200
250
300
350
400
450
Temperature (K)
1. Which is evident in the graph above?
a. As temperature increases, pressure
decreases.
b. As pressure increases, volume decreases.
c. As temperature increases, the number of
moles decreases.
d. As pressure decreases, temperature
decreases.
d
2. Which behaves as an ideal gas?
a.
b.
c.
d.
Gas A
Gas B
Gas C
Gas D
d
Increasing the pressure above 200 atm raises
the temperature.
b. How do you think lowering the temperature
of this reaction below 450°C would affect
the amount of time required to produce
ammonia?
Lowering the temperature of this reaction
slows the rate of reaction, increasing
the amount of time required to produce
ammonia.
Solutions Manual
Chemistry: Matter and Change • Chapter 13
273
13
SOLUTIONS MANUAL
Use the graph below to answer Question 3.
Temperature (°C)
Density of Air
Determine the molar mass.
1 mol Na 22.99 g Na
__
22.99 g Na
1 mol O 16.00 g O
_
16.00 g O
1 mol H 1.008 g H
_
1.008 g H
200
160
120
80
40
0
0.80
1.00
1.20
1.40
Density (kg/m3)
3. The graph shows data from an experiment
which analyzed the relationship between
temperature and air density. What is the independent variable in the experiment?
a. density
b. mass
c. temperature
d. time
1 mol Na
1 mol O
1 mol H
Total molar mass 22.99 g 16.00 g 1.008 g
39.998 g 40.00 g/mol NaOH
Determine percent by mass.
percent Na __
percent O 16.00 g/mol 100 40.00%
40.00 g/mol
__
percent H 1.008 g/mol 100 2.52%
40.00 g/mol
Use the circle graph below to answer Question 6.
Hydrogen
4.21%
c
4. Hydrofluoric acid (HF) is used in the manu-
facture of electronics equipment. It reacts with
calcium silicate (CaSiO3), a component of
glass. What type of property prevents hydrofluoric acid from being transported or stored in
glass containers?
a. chemical property
b. extensive physical property
c. intensive physical property
d. quantitative property
a
5. Sodium hydroxide (NaOH) is a strong base
found in products used to clear clogged
plumbing. What is the percent composition of
sodium hydroxide?
a. 57.48% Na, 60.00% O, 2.52% H
b. 2.52% Na, 40.00% O, 57.48% H
c. 57.48% Na, 40.00% O, 2.52% H
d. 40.00% Na, 2.52% O, 57.48% H
c
Chemistry: Matter and Change • Chapter 13
Lithium
28.98%
Oxygen
66.81%
6. What is the empirical formula for this
compound?
a. LiOH
b. Li2OH
c. Li3OH
d. LiOH2
a
Assume a 100 g sample.
Determine the number of moles.
66.81 g O 1 mol O
_
4.176 mol O
28.98 g Li 1 mol Li
_
4.175 mol Li
4.21 g H 274
__
22.99 g/mol
100 57.48%
40.00 g/mol
16.00 g O
6.941 g Li
1 mol H
_
4.177 mol H
1.008 g H
Solutions Manual
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CHAPTER
CHAPTER
13
Calculate the simplest ratio of moles.
4.176 mol O
__
1.000
4.175
4.175 mol Li
__
1.000
SOLUTIONS MANUAL
10. The diagram below shows the Lewis structure
for the polyatomic ion nitrate (NO3). Define
the term polyatomic ion, and give examples of
ions of this type.
4.175
O
O N O
4.177 mol H
__
1.000
4.175
The empirical formula is LiOH.
7. While it is on the ground, a blimp is filled with
L of He gas. The pressure inside
5.66 the grounded blimp, where the temperature is
25°C, is 1.10 atm. Modern blimps are nonrigid,
which means that their volumes can change. If
the pressure inside the blimp remains the same,
what will be the volume of the blimp at a height
of 2300 m, where the temperature is 12°C?
a. 2.72 106 L
b. 5.40 106 L
c. 5.66 106 L
d. 5.92 106 L
106
Use the table below to answer Question 11.
Radon Levels August 2004 through July 2005
Date
Radon Level
(mJ/m3)
Date
Radon
Level
(mJ/m3)
8/04
0.15
2/05
0.05
9/04
0.03
3/05
0.05
V
V
_
_
10/04
0.05
4/05
0.06
11/04
0.03
5/05
0.13
T1 25°C 273 298 K
12/04
0.04
6/05
0.05
T2 12°C 273 285 K
1/05
0.02
7/05
0.09
b
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
A polyatomic ion is an ion made up of more than
one atom that acts as a single unit with a net
charge. Other examples include hydroxide (OH),
chlorite (ClO2), and cyanide (CN).
1
2
T1
T2
V2 __
(5.66 106 L)(285 K)
5.4 106 L
298 K
8. Describe several observations that provide
evidence that a chemical change has occurred.
Evidence of chemical change includes temperature
change, color change, the production of an odor
or a gas, and the precipitation of a solid.
9. Identify seven diatomic molecules that occur
naturally, and explain why the atoms in these
molecules share one pair of electrons.
11. Radon is a radioactive gas produced when
radium in soil and rock decays. It is a known
carcinogen. The data above show radon levels
measured in a community in Australia. Select
a method for graphing these data. Explain the
reasons for your choice, and graph the data.
Students should choose a bar or line graph for
the data, with justification that each data point
can be represented on the graph.
Hydrogen (H2), oxygen (O2), nitrogen (N2),
fluorine (F2), chlorine (Cl2), bromine (Br2), and
iodine (I2) occur naturally. By sharing a pair
of electrons, both atoms achieve noble gas
configurations, resulting in atomic stability
Solutions Manual
Chemistry: Matter and Change • Chapter 13
275
CHAPTER
13
SOLUTIONS MANUAL
12. Which diagram shows the relationship between
volume and pressure for a gas at constant
temperature?
V
a.
V
d.
P
P
14. Assuming ideal behavior, how much pressure
will 0.0468 g of ammonia (NH3) gas exert on
the walls of a 4.00-L container at 35.0°C?
a. 0.0174 atm
b. 0.296 atm
c. 0.0126 atm
d. 0.00198 atm
e. 0.278 atm
a
nRT
_
V
(0.00275
mol )(0.0821 L atm/mol K)(308.0 K)
____
P
V
V
4.00 L
b.
e.
P
= 0.0174 atm
P
V
c.
P
d
13. The reaction that provides blowtorches with
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
their intense flame is the combustion of acetylene (C2H2) with oxygen to form carbon dioxide
and water vapor. Assuming that the pressure
and temperature of the reactants are the same,
what volume of oxygen gas is required to
completely burn 5.60 L of acetylene?
a. 2.24 L
b. 5.60 L
c. 8.20 L
d. 11.2 L
e. 14.0 L
e
Balance the chemical equation: 2C2H2 5O2 0
4CO2 2H2O
Determine the volume ratio:
VO 5.60 L C2H2 2
276
5 volumes O
__
2
2 volumes C2H2
5 LO
_
14.0 L O
2
2 L C2H2
2
Chemistry: Matter and Change • Chapter 13
Solutions Manual